When I first got my lathe I just set it all up and started to use it as it was, figuring that I would eventually make do mods and tweeks.
The only thing I have done up to now is replace the headstock bearings with tapered roller bearings and that was a plus that paid dividends. I took a cut on an old cut off 5/8" high speed steel reamer shank today. I was able to take a cut of .100" on a side or .200" on the diameter feeding by hand and it cut like butter without chatter like I had before. I was using a carbide inserted lathe tool that had 5 degrees side rake and spinning at about 1200 rpm. This is one mod that I definitely can recomend doing. I also calculated that the factory supplied gearing for the power feed on this lathe feeds at .0039" per rev of the spindle in case anyone wanted to know.
The leadscrew on my machine did not rotae freely so I looked into it yesterday. I took the leadscrew out and checked the journal areas and found them to be quite a snug fit in the bearing blocks. I chucked the leadscrew in the chuck and carefully polished the journals down so they were a free fit and put the leadscrew back in and it now works freely. At the same time I decided to clean up the gear train and spend a little time to make sure all was working as it is a part of the leadscrew drive system. I had to move the detent holes for the tumble reverse as others have done and that turned very well also.
So many things I want to do and so little time!
Dick
OldToolmaker