If you had access to a mechanic that did emissions testing and repairs at a LA municipal fleet garage or a Cali state fleet garage would you take his advice? I would, and you have that mechanic in @db4690. He has years of experience solving problems like yours for cars, big trucks, and small trucks like yours.
Get a capacitor ignition system. Hot spark under all conditions. And since you still have the original ignition components installed, a simple toggle switch puts you back into the original ignition system.
Smog Check Manual - California Bureau of Automotive Repair (PDF)
Ignition Timing Test
Pass/Fail Criteria: To pass inspection, the base ignition timing must be within 3 degrees (± 3 degrees) of the manufacturer specification. If it is more than 3 degrees from manufacturer specification, the vehicle shall fail the functional test.
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Thanks, I will look into it as a possible last resort if the truck fails emissions with the setup I have with the new ignition parts.
The PerTronix 40011 coil arrived. The primary resistance reads 1.3 ohms using three different meters. The PerTronix website specs the primary at 1.5 ohms. I find it strange that the PerTronix website does not spec the secondary resistance, only that it produces 40,000 volts, and that Summit Racing does spec the secondary, at 10,600 ohms. The one I received reads 9,840 ohms on the secondary. I guess the most important number is the ratio of primary to secondary, and that the primary resistance is within the the factory specs. The meters I have do not read to hundreds of an ohm, so canât determine if this coil is within the 1.34 to 1.55 range that the shop manual shows. It could be as low as 1.25 ohms, rounding up to 1.3.
Oh wellâŠ
When I replied to db4690 I was not aware of his status. If I were aware of it, I would still ask the question, even more so. How else is one to learn?
Jack
I expect your 87 Dakota already has a capacitive-discharge (i.e. electronic) ignition system. Thereâs no ignition points requiring periodic replacement inside the distributor, right? You should be good to go on. You wonât be able to measure low-ohms accurately, suggest to just presume Pertronix has already tested the primary resistance is correct for your new coil. The maximum spark voltage is probably limited by the spark plug gap on your truck, not the coil. Tx for the info on the +/- 3 degrees 
Thanks for the push to confirm this. I really canât say how I originally learned it, but given Californiaâs tendency to make the test more difficult to pass nothing can be assumed.
The timing is electronic and the distributor has no points.
Here is something that PerTronix says on their website about this coil "Higher voltage allows larger spark plug gap for added power, smoother response, and improved fuel economy. The shop manual specs a plug gap of .035 inches. I was thinking of over-gapping them when I read this, but then realized that this particular coil is very similar to the stock coil in terms of primary and secondary resistances. One question that crops up is whether or not there are other factors that determine the maximum voltage of a coil besides the primary and secondary resistances.
The autotransformer coil for an ignition system will continue to build voltage until a breakdown occurs. The idea is for that breakdown to occur at the spark plug gap. A coil specified to handle a higher voltage is also designed with more robust dielectric qualities to ensure it survives under those conditions. If you widen the gap, any coil will produce higher voltage. The key is when they are designed to reliably support it.
There is a lot more to the magnetics design than most people might think. How much energy can it store and deliver to the load once breakdown occurs? If you simply widen the gap on the standard coil, you may not get much more energy delivered because the design of the coil is maxed out. All youâll get is a slightly delayed ignition spark and a high voltage puncture of the insulation at some point down the road 
Wow, very good information! Thank you so much for that!
Jack
Have you tried the NGK V-groove spark plug? The groove is designed to produce a more robust spark and more complete combustion. Iâve found by trial and error that changing to NGK V-grove spark plugs to be very useful in getting my Corolla under the HC limit. Doesnât help a lot, but sometimes you just need a 5 ppm improvement.
This is the first I heard of it. I am going to go with what I have at the moment, new stronger coil, new brass cap and rotor and new quality plug wires, and retard the timing instead of advancing it, as I have done in the past., which, along with the weak coil, could have been the biggest factor in failing. I surely do not know how I got it into my head that advancing the timing lowers HC emissions, but very happy to be corrected on this by davesmopar. I will drop it from stock 7Âș BTDC to 5Âș BTDC. Previous I would set it as high as 9 or 10. I am allowing myself to have some hope that I will pass on the first try this time.
My pinhead reasoning for retarding the ignition timing to improve HC emissions is that the longer the O2 molecules can linger in the cylinder with the gasoline molecules, the more likely theyâll be paired up with each other when the spark occurs.
Why Retarding Spark Advance Reduces HC Emissions
This article I referred to earlier speaks to the reason why retarded timing lowers HC emissions. I have found this backed up by some scholar-level papers on the subject.
I installed the new coil, cap, rotor, and wires. In the process I pulled the plugs to widen the gap from .035" to .040". The plugs are relatively new. I donât drive the truck that much anymore. Tomorrow I re-jet the carb to get a leaner mix, retard the timing two or three degrees and set the curb idle rpm to spec. And then it will be as ready as I can make it for the test.
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It appears that you have reached the lean limit. Leaning the fuel mixture further will reduce CO but HC and NOX will likely increase.
Reducing spark advance will make a difference, I have had success with this on my older vehicles. There is no functional test or ignition timing inspection in Nevada, so I am able to make greater changes.
On a VW, I set base timing at top-dead-center, reduced HC by more than 50%.
An old Mopar with a performance camshaft, I disconnect the vacuum advance, this reduces HC by 75%.
Changing your ignition timing from 9 degrees BTDC to 5 BTDC will make a difference.
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I donât think I have. When I pulled the plugs to widen the gap by .005 inches I was surprised to find they had a dry black soot coating that indicated a rich mix. I need to check to see which size main jets I last put inside the carb.
I sincerely hope so!
Isnât that dry black soot from before you did all the upgrades??? If so then you donât yet know the effects your new combo will have on the plugsâŠ
Looking at the smog test results you posted previously the engine is already running on the lean side, possibly too lean. Further jetting the carb down will likely result in raising the NOx and HC readings.
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Good point. I should probably take the truck out on the freeway an burn up a gallon of gas and check again.