you have come this far so dont goober it up on the hickabilly bolt/nut trick.

pull the cover or the pan and put a helicoil insert into the t-cover,make sure to remove the tang on the coil before running the bolt thru it.

I have a cover that both holes have been done this way for a long while now.

my one SB alum intake has had a helicoil put into every bolt hole with threds on it.

fix it once and be done with it. you dont want a goober nut/bolt on a nice painted engine.