Many years ago, I tore the engine apart to rebuild it to a fresh start. I chose this not because the engine didn't run before I stored it, but because the entire jeep was getting a full rebuild and I wanted to "reset" the engine as well. This turned out to be a good idea.
I had a flywheel bolt back out due to nut failure (this is another story) at some point when I was still driving it around. That bolt spent the rest of its life banging around between the back of the block and the crankcase flange. When I disassembled the engine, I could see there was a lot of damage; hairline cracks and chips in the block around but outboard of the rear seal. I got a shop to weld/grind that damage and feel it will hold - time will tell.
Moving forward on that rebuild, I sent the block/head in to have it prepped for rebuild. Although I anticipated the head would get resurfaced, I didn't discuss decking and assumed it wouldn't be done. It was. When I picked up my block, I noticed the engine serial number was removed. I didn't address it at the moment but reassembled the engine, mounted it on the frame and forgot about it.
Fast forward to this year. Since I'm not immune to having senior moments where I second guess myself, a concern popped into my head where I couldn't remember if I'd washed the debris out of the cylinders from the honing process. Once I had removed the head and pistons, did a quick wash to verify (it was done) - I began to look at that flat empty boss at the front of the block since the head was out of the way. I re-engaged my research and found a reference to punches from a company that will sell custom sets (I needed a numbers set and the letter, "J").
http://www.columbiamt.com/store/Machine ... mps31.html
I then reviewed several tutorials on metal punching or stamping. The punches arrived and I marked the boss and tried the first digit.
After the first attempt, I noticed it wasn't deep enough. Following the video guidance on how to "re-punch" a character I got a much better result.
I finished the serial number and reattached the head and valve cover.
Since the re-stamping process chipped and removed the paint in a jagged way, I eventually came back to this to add paint across the completed serial number. This project took a long time but my engine finally has its "identity" back!