Among chevys infinte revisions over the last 30 years on the small blocks, is there 1 size only for the oil pump bolt? The pump bolt from my 87 305' seems atleast 1/4" too long on this new 1980-1985 350 block. Pump bolt bottoms out with atleast 1/4" left.

Not sure on length, but if you bottom out the bolt, it will bottom out against the main bearing in the cap. You must be sure that it does not contact the back side of the bearing. I also seem to recall that the pump bolt is very close in length to the outter main cap bolts on a four bolt block. I havent played with this stuff in over 10 years maybe 15...

You got it mixed up with a short head bolt .The oil pump bolt is the only one that is that lenght. I know Don't ask.