'51 Build w/4bt Cummins

[II_Slow]

If you haven't found the 4BTswaps.com forun yet, go there for diesel specifics. Lots of expertise there on those engine over there, and you'll find all of the expertise on the early Chevy here (not me, I'm the receiver of said expertise!).
Should be an awesome build. And as others said, go ahead and box the front half of that frame while you've got everything apart. Should be easy now. If you are like me, positioning parts where you want them for welding is 10x easier than welding overhead or trying to reach around other stuff.