Cant tell you the casting number meaning but long block or short block means is it with heads or with out.
if you get a new long block that means engine block with rotating assembly and cylinder heads installed. short block is just the block with installed rotating assembly. both these terms are used to describe replacement / rebuilt engine options.
have you tried googling the casting number? A few things come up on ford/ mustang sites but i dont know ford stuff well enough to point you in right direction
I did yes and it came up 1972 302. I have been in contact with a crate engine company and there ford blocks don't have same casting numbers but I guess it doesn't matter as long as it fits. Wich I've been assured it will
