Cool, it should stick fine. The beauty of POR15 is it looks great as is, but can be top coated if preferred. I haven't top coated it yet since i like the gloss finish and my cutlass won't be a daily driver. If it was a daily i would use something over it.
Breaking bolts is common on our cars, most of mine came out fine, except all 4 trunk bolts. I had to cut 4 holes in the trunk to access the top halves, then just replaced with longer bolts and metal top lock nuts.
If you wanna see more pics, search "87 cutlass efi build thread". I don't wanna clog up your thread with pics buddy as i have plenty of them showing before and after POR15.
If you have any questions about it, just ask. Me and my brother n law use it all the time, and have been using it for about 6 or 7 years now....his garage floor has the evidence to prove it lol!