Hopefully you can get the manifolds off without breaking any bolts. Mine had broken bolts before I started. I ended up taking it to a shop. $8000.00 later, I had headers installed. They tried to drill them out, but couldn't. They ended up pulling the heads. When they went to install the rebuilt heads, there ended up being an issue with the lifters. Several of them stuck. So the heads came back off, lifters replaced, and everything put back together. It was about worse case scenario.
2004 AllegroBay 34XB Nov 2017 Banks, Front & Rear Trac bars, Konis
Sold:'83 Revcon Prince 31' FWD GM Performance 502 w/Edelbrock MPFI, Thorley Tri-Ys & Magnaflows, 4L85E 4 spd