Am i crazy?

FYI, an 8-1/4 will hold up to 400 HP without issue and live a long time for a fraction of the 8-3/4 price. Sell the rear and get another. Collect parts and stash them someplace that they'll stay good. When you get the whole package of parts to do the next step IE; rebuild trans, engine, exhaust,etc... Then assemble it and and put it to the side until the whole package comes togther. Take your time on the whole thing.