Standup, there are basically 3 cranks a long snout 12 counterweight(the 76 will have that), a long snout 4 cwt, all the Eagles should have that, and a short snout 4 cwt that the later Wranglers etc had. If building a stroker the short snout is usually slightly preferred(though the early 12 cwt is reputedly slightly stronger and and with 20lb more weight should be slightly smoother running ), but any will work with a 10 mm spacer that can be made by cutting a chunk off an old harmonic balancer. The mounting bosses would be the only possible stopper, I just don't know the answer to that as I'm always dealing with later blocks(4.0's)