I have been given an old Bachmann HO Union Pacific no 824 which I believe is a U36B. It runs reasonably well so I was wondering if the chassis fits any better quality and more prototypical bodies (preferably IC/ICG types or anything that could run in Illinois). I am not looking for perfection, just like to make use of junk!
The Bachmann U36B is a very good representation of the prototype. The hand rails need some work, and some other minor detailing. The shell is much better than the chassis. Many people put this shell on a narrowed Athearn B-boat chassis (narrow replacement motor or narrow Athearn motor required due to scale width hood). Nowadays, a Bachmann B23-7/B30-7 chassis would be a good substitute.
The chassis was considered junk.
The U36B and U33B (depending on phase) are externally identical. Rock Island had some late U33B, which ran in Illinois.