I have this problem with only one of the bolts on my cover, the one closest to the driver, up near the firewall. I just left it in place and not screwed in. It's a little frustrating to have everything in place except for this one bolt. Will be looking for your resolution. Thanks.

jcyuhn's solution seems right. I'll look for longer metric bolts (5mm is about 1/4 inch) when time permits.
regards to all,
Mark

Only 3 of the 6 bolts will get tight. One of the bolts looks like it has the remnants of a helicoil or something of that nature. I've seen some comments that say the cover is not needed. I say bull to that. The cover serves as a direct hold down for the coils and a element cover. The rubber wires and boots wouldn't last very long subjected to dirt, road grime and moisture. I'm all for the helicoil method of securing. Without the bolts holding the coils down they seem loose.

Rick Potter

I just repaired mine a couple of weeks ago with Helicoils. One was stripped due to the dealer overtightening then some years ago. I ended up doing all 6 while I was at it.
I didn't feel confident drilling the holes by hand on the vehicle so I removed the valve cover and used a drill press. I measured the depth of each hole and where the thread started as each hole was different due to the shape of the cover. Drilled, tapped, installed Helicoils to measured depth and finished the job by getting rid of the rusty bolts and installing stainless allens.