One thing- not ALL the '87-up blocks are provisioned for roller cams. I have a '92 truck 5.7L engine w/swirl port TBI heads and NO bosses for the spider, no machined lifter bosses, no cam retainer bosses, etc. Not just untapped- un-there! lol
The breakdown goes like this (be aware there are ALWAYS exceptions):
For 350 flat tappet
blocks look for casting number 10054727, 14079287, 14088548, and 14101148.
For 350 roller tappet
blocks look for casting numbers 10243880, 14011148, 14088526, and 14093638.
There are '87-up blocks that have the full provisions for a mechanical fuel pump, but they're relatively rare. Most often they're the earlier blocks and blocks that are equipped w/flat tappet cams.
Something to watch out for: There's a flat tappet block AND a roller block that both end with the numbers 148. 14101148 is a flat tappet block, 14011148 is a roller block.
About the quickest way to tell if you are looking at a roller engine in the junk yard, is to pull a valve cover and remove a push rod. Flat tappet p-rods are about 7.8”, roller p-rods are much shorter at 7.2” long.
, there's no 'good' and 'not as good' blocks, other than 2- and 4-bolt mains.
Hope this helps!