You also need to be very careful with this type of cleaning product around various plastics and rosins as they can melt them, they also remove the images on tags, and information printed on products. So, as the warning on your spouse’s favorite piece of clothing goes, “test it in an inconspicuous spot…” Just do not spray it down…
What?? You mean like the time I really needed the info from a tag on a transmission and sprayed brake cleaner on it and then wiped ALL the information off the tag?? Oops!! I don’t know what you are talking about… 
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Plug gap specification is .043
Old plugs were at .048, .049, .052, and .053.
I do not know if the larger gaps on the old plugs would have been an issue. But since I was changing the coils I changed the plugs too, since they had 5 years and 90,000 miles on them.
Seems there was considerably more than a 10% increase in the spark plug gap; that could indeed have damaged or stressed the coils. The next question is why? You’ve a seen the claim here (above, post 16) that iridium plug gaps do not change at all, or only a minor amount in 120K miles. A couple of seemingly implausible reasons for the large increase in gap over just 90K miles:
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Maybe the plug gap didn’t change, but was incorrect when they were installed originally.
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Maybe the original plugs were counterfeit , not iridium
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Did you check the gap on the 5 year old plugs before installing them… I have seen that much difference, which is not a lot, on new “pre gapped” plugs out of the box… I don’t care what anyone says, I always check and set plugs no matter what with single ground electrodes…
This is a worn out plug and yet the vehicle had NO running issues or lights on, pure maintenance, just took picture to show customer…
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My only experience is w/copper plugs, easy to set the gap manually. But I’ve heard said it isn’t possible (or even a good idea to attempt) to try bend anything on an iridium plug to adjust the gap. Material is too stiff & too brittle. Can you really bend iridium plugs to set the gap?
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Yes, but you need to know what you are doing and have the correct tool… I have never had an issue…
I have an old Snap On one similar to this…
Here is a video on how to…
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Yes, I check the gaps even though they are pre gapped` Below is a photo of the plugs. Number 2 was the plug that had the faulty coil.
Full size image if you want to really zoom in is here.
@davesmopar - that was an informative video. I had heard the coin style spark plug gapping tools could be problematic, but did not know why.
It appears from the vdo we diy’ers can bend the ground terminal (bottom leg) on iridium plugs all we like, just so long as we don’t disturb, rub, or otherwise put force on the center electrode. Good to know, concur, thanks for posting the vdo @davesmopar 
Just remember that just checking the gap can damage it if done wrong and not careful enough…
And bending the ground electrode enough will weaken it, so not all you want… lol