It's a safe bet to use the Ford 9 axle. From the GM rear failures I have seen at the dragstrip I would not use a 10 bolt GM in anything with even mild performance increase. Whenever I see a GM axle in a streetrod I always have to ask, "what else did they cheap out on". The problem with the GM design is the "C" clips. If the axle breaks, (and they do) the wheel, drum and axle leave the vehicle making your ride a tricycle. NHRA wont let you run a GM rear in the faster classes without a C-clip eliminator / axle retention modification. That should tell you how weak they are.