360 block

There is a debate that 1971-74 360's can have cylinder walls that are more thick. These would mostly come from C-bodies and 1974 from A/B/C bodies. Since you were considering a Ritter block, I would ask Mike from MRL, Brian from IMM, Rob/RAMM, or Ryan Johnson from the Shady Dell -they probably have 360 cores already, some of them probably have R1/R3/X/340Reproduction blocks for sale. If you get an older block, obviously get it sonic checked for the power levels that you want. Bloomer has the 4.125 and 4.25" stroke cranks and hughes has the 4.18" crank I believe. Yellowrose was right though, the X and other blocks are popping up on craigslist ( my-craigs-finder.com ) or facebook