1st Gen blocks
 

What year blocks are interchangeable with the 1993 5.9 block? Im thinking about slowly building a replacement, so when the time comes, Ill have a fresh replacement ready..

Just the lower end block is the same '89-'98.0.
If you also mean with the head on it as well, then the head is different '89-'91.0 than the '93 head.

In '94 the injection pump and injectors change, so the later heads would need the injectors swapped.

Oh and if you need a Cummins 12V motor, I have dozens of them in my shop.

Oliver, how's it going? I recall something about a Brazilian casting that was inferior, is that true?...Mark

It is going great!
Yes there is a Brazilian block known as the 53 block.
I usually see them on the 24Vs.

Nice supply Oliver. I may take you up on it. Ideas on prices? A complete head and block suitable to rebuild is what I kicking around.