That describes my 1994 F150 pretty well, too: the 4.9L inline 6 is SAE; the rest of the truck, metric. The Mazda-derived M5OD tranny is metric, but works somehow with the engine.
Just make all the bolt heads 19mm (3/4"), 13mm (1/2"), and 8mm (5/16") and you’re good to go.
;-]
I have an torque wrench with an electronic readout, and more than once, I’ve had to reset the meter to read “foot/pounds” because the unit of measure had been accidentally switched. That’s why I always double check it now before I use it.
The Gimli Glider was retired in 2008, and is sitting in the Mojave Desert. It was put up for auction in 2013, but the minimum wasn’t met and so it sits.
Instead of wasting server space on a gazillionth tire pressure/ gauge thread, I’ll submit my recent experiences with a digital tire gauge here:
In 2021, I purchased the 100psi model of JACO’s Elitepro digital pressure gauge. On Amazon and other online brokers, it is consistently in the top ten, ratings-wise, among electronic tire pressure gauges.
CONSTRUCTION:
As sturdy as one could get for a moderately-priced digital tire pressure gauge. All physical members(chuck, hose, and dial head) swivel independently, making it easy to access any tire valve, save duallys, for obvious reasons.
OPERATION:
The JACO Elitepro 100 and 200psi kit are AAA size battery powered, easily accessed by a snap-clip door on the back side of the dial head. I would recommend replacing the batteries on digital tire gauges once per year, regardless of how often you use them. Every 6 months, if you engage in off-road or other activities where you adjust tire pressures frequently.
The left button(On) powers up, resets old tire pressure readings, and powers off the gauge. The right hand(Units) button cycles through the pressure scale of your preference: PSI, kPa, Bar(kPa/100) and kg per cm. The gauge (should) power itself off automatically, after several minutes of no activity.
I am unsure how to use the ‘HOLD’ feature, and holding down the Units button for any length of doesn’t seem to do anything.
Now to the order of business - obtaining a pressure! 
Once the JACO is on(blue backlit display visible) simply chuck a tire valve as you would with your other gauges. Within two seconds, a steady current tire pressure will display, down to tenths PSI by default.
Pressing the bleeder valve on the brass neck will, obviously, bleed air. After a slight delay, the adjusted pressure should display.
Advice: Since this is a very precise, high-res. device, bleed air out slowly, and after counts to ten. The value tends to drop slightly below your target value, and may stop slightly above it.
EG: Bleeding down to a target of 33psi:
PSSSSS!
(count to ten)
33.7
PSSSSS!
(count to ten)
33.2
PSSSS!
(count to ten)
32.9…33.0…33.1.
PS! (a shorter bleed this time)
(count to ten)
32.9…
33.0!
On to the next wheel.
In short, patience is a virtue with this digital gauge, as with my Longacre Basic Digital gauge I also bought around the same time. That one resolves down to one-fifth psi (33.8 > 33.6 > 33.4 and so on), and, also measures in kPa and Bar.
Both read half to one PSI higher than my personal gold standard - Longacre’s ‘Magnum’ 60psi edition, with a 3.5" diameter dial, 4 inch diameter overall with rubber bumper covering.
PROGNOSIS:
With digital gauges, as with anything electronic, it will take more time to dial in your target tire pressures. For me, it’s a lot easier and honestly a lot more reassuring to set cold pressures with any of my analog Longacres, of which all are easy to see where the needle points and stops.
Yes, I can share a similar experience with you. A while ago, I had a similar incident where I misread the pressure on my car tires. It was also a cold morning, and I noticed that one of the tires seemed significantly low. Concerned about the pressure, I quickly grabbed my tire gauge to check the reading. To my surprise, I saw a reading of 18.5, which was well below the recommended pressure. I immediately started to worry about how it could have lost so much air without any indication from the TPMS 