This is a NOVA site, so it may not be accurate for a pickup engine, but worth a look anyway.
http://www.novaresource.org/codes.htmHEI is a later distributor, but a good one to have. The heads for the inlines were all the same with a few different part numbers for the 230-250-292 engines, so don't go by them, same for the block casting numbers, 230 and 250 used the same blocks, just different cranks and pistons. You can make a 230 into a 250 with the right parts. Best way to tell the difference is the piston tops, 250 is dished, 230 flat, 250 has a longer stroke also.
