You could take a bolt that's way to long, run it down till it bottoms out, mark on the shank with a thin permanent marker or scribe with washer in place. Check the other holes also with that mark, and then give your self a little leeway so the bolts wont bottom out. Another way to look at it, you would want at least 3/8" minimum thread engagement into the stand I would think. You might check on ARP's site and see what they list it as too.
No help here,...I run allen head studs in a Stage V head with al stands. 3 studs would hit stock valve covers in the #1 & #8 cyl area baffles because the studs stick up higher than the nuts. Even though I shaved those 6 studs I ended up with Stage V covers which clears.
