So in the process of removing the cylinder heads and completely disassembling the motor, 3 cylinder head stud nuts stripped and would not come loose.
Lots of lube and still no good. The rusted heads stripped in the inside before they would let go. So, cleaned the nuts, dried them well, put some burnishing paste in the hole to add to grip and retried the allen head nut removal tool.
Better!! Got 2 out of the three removed.
The last one is seriously stuck.
Ordered an ERWIN tool set with fat reverse thread removal bits to remove the stubborn nut. Once they came in, the final nut eventually gave way, but dang!! SO much force needed.
Turns out I have half steel, half dilivar head studs in the block.
Here's the offending party!