I found this retro Shimano 600 crankset in the parts bins, complete with its cartridge BB bearings.
It is a 53 - 39 so a bit wider range than the 52 -42 it replaced. Funny thing though, the stock one was pinned and ramped, this one isn't. Well at least it is lighter since it has alloy chainrings as opposed to steel ones on the stock version.

It is true what they say about how some of these bikes are assembled, everything was supper tight and there was hardly any grease in the bearings.

Also added some SPD pedals.