I needed to reduce a piece of thick wall steel DOM tube by 0.5 mm to about 38 mm. It's 153 mm long. In order to fit it on the lathe I retracted head spindle past the stop screw. Then I made a hollowed plug fitted into the end of the tube to accommodate/recess live center of the tail stock. The part barely clears the cross slide.?
Finish leaves a lot to be desired, but it did the job.