Help with Slant 6 oddity identification

So, going through cores acquired during my son's slant 6 turbo efi build and I have come across a few things about which I can't find information.

I have two forged crankshafts with NO casting numbers that cross reference.
Crank number 1 has a 13 on a throw and the number 70 on another throw. No other identifiers
Crank number 2 has a B on one throw and a number 28 on another. No other identifiers.

Both cranks have a 2.15 rear register for the flexplate but all six holes are evenly spaced. Which I believe there is no aftermarket flex plate for as they are not offset?

I have a 3 freeze plug block casting number 2463430-19 with a passenger stamp of IND225-R-2722080. This was painted orange and I kept the Chrysler Industrial Tag because it was cool IMO. This was the block we were going to use for the turbo build but went with a BH ribbed clock with 5 plugs instead.

Anyway, this block came out of a propane powered Massey Ferguson combine and is SUPER clean and has been magnafluxed good with the bores appearing to be able to work with just a hone job.

Does anyone know anything about the cranks above and why one of them could not be used in the above block for a stock build?

Thanks in advance!