[misfit41]

I think your right about the crank,it is different.the marine blocks are the best 427 {fordmfg}blocks out there,they have very high nickle steel like the c5 and c6 blocks,contrary to the adds I see on ebay,the c8az G service block is just iron like a 390 ,not as strong as a marine,the marine block also has .125 thick cylinderwalls,compared to .080 in most others.it will satand up to more bore,and much higher compression.Tk