Ford blocks and all other parts have engineering numbers cast or stamped into them (depends on the mfg technique used to make the part) This number is located in the lower rear of the block near the starter.(here's one example: C9OE-6015-A) Roller blocks have it cast here, but in a different location than the flat tappet blocks(and will just have the prefix: E6SE, F1SE, E7TE). Just me, but a roller block is the only way to fly, unless you're going all out racing, then the older flat tappet blocks seem to have a better reputation as to strength, these are the late 60's to early 70's blocks, with one exception, the late 70's D8VE block, this one's thick all over like the Mexican block (late 60's to early 70's castings made in Mexico) With the roller blocks, the only one to fight shy of is the 85 castings,starting in 1986, Ford added more iron to the block with the E6SE castings. All others since have the extra iron. As for Id'ing a C-4, these had removeable bellhousings and all three main castings (bell, case and tailhousing) are aluminum. This is the only Ford auto trans with these features. You can also help yourself more by buying all the Ford motor manuals and read more. I learned from these manuals combined with tearing down many motors and building a few more.