Nope. Acid can possibly raise the codes for you to see but why bother? It's just another block now.
If you are worried that it might have been original to the car, you can get the date code of the casting and post the number in the "Tag Team" section. We can tell you the date the block was cast and that should be within a couple of weeks of the body build date. The block casting date code is on the rear top surface behind the . It is cast into the metal, not stamped into it. It is usualy a single letter followed by two or three digits. The digits are about 3/8" tall and look like they were held in place with a couple of screws in the mould.