1974 Duster

I have the motor out and tore down. It has been into at some point. Has 587 heads with stock valves. Does have aftermarket springs, and sure cam. The bad part is it is .060, so I now have 2 .060 340 blocks, guess i'll try again. The bore looks nice with no ridge and looks like a nice set of pistons they come out of the deck just a little maybe .010 or so, 4 valve reliefs. And as for the VIN on the block that I couldnt wait to see. No numbers at all just a blank pad, is this something that is common?