Block casting number search

I have no real info on this piece, other than my speculating that it must have been cast after the mid '80s shift to hydraulic-roller capable blocks (LA). The thick-*** deck would allow it to be machined-down to 9.2" deck, but it has the wrong water pump inlet holes (they would have to be the "D" shaped ones to seal if decked that far), so that's out. I think all the MP blocks of that era had the 48*-capable lifter bosses, so if the bore is already over 4", I'd suspect the 340 replacement. I think they offered a sub-3.91" unit as well, for 318 applications. Nice piece, regardless!