I’m thinking this motor was an ATK or Jasper rebuild possibly, they stamped the pan rail, the crankshaft, etc. Cast crank and rods are scrap, main & rod bearings are both stamped .040 (wow, turned .040/.040), stock rods have already been reconditioned at least once or more? Keep pile on this one is the block, pistons, balancer, flex plate, tins, and the serpentine belt system, it's a score if the block is good!
Build date stamp on this block is T1222ASC T=Tonawanda, December 22nd, ASC= 1988 Truck 454 MT L-19 TBI Vin N, 30