[Mart]

I'd probably go the other way and helicoil it. The flywheel bolts are drilled for safety wire, there is no reason to bend the plate up. The bolts are a fine pitch. Unless you went for a fine pitch metric you might not get the loading you need. The flywheel bolts are a highly critical item, they need to be right. A helicoiled thread is no weaker than the original thread in the parent metal.

Ideally you wouldn't want to have to use either remedy, but my gut feeling is that a helicoiled repair and keeping the bolts and flywheel stock would be the preferred method.

Too thick a bolt head can cause problems with the clutch plate too.

Mart.