I have a clean truck for an 88, my brother owned it for 8 years and i have had it for 2 now. I purchased banks headers and have yet to start the project but it is on the horizon. Would anyone think it to be crazy if i cut the heads off of all the manifold bolts, got the manifolds off, then used a 3 jaw extractor to remove the remnants of the bolts. My fear is the bolts may snap recessed into the head and i would spend a lifetime removing them. If i have a complete bolt shaft to grip with the extractor i feel it may be a good method as the manifold would (hopefully) already be out of the way and not put any extra resistance on turning the bolts. Had a bad experience with the timing cover/water pump bolts and the extractor was a godsend. I work in the automotive field and used to work on German cars for a living so i'm not concerned with doing this job, just the unknown things that could lay ahead.