In another post https://ogrforum.com/d...nt/12129987962608355 some of us discussed the use of reversing your trains.
Yet again, I posted on the site showing that with work/modifications on the wheel sets of PW cars and the MTH switches, I was able to back 8 PW cars in circles through even O31 switches.
I thought I would post a picture of one such modification to an O31 switch, using a small piece of wood. This is prior to painting it gray to match the unit. It seems to help keep the PW car's wheel sets in line better.
It starts out square, and then I "fine tune" it (if you can really call it that) with a utility knife. Takes a little patience, but perhaps you should try it if you are having trouble keeping your wheels on the track while backing. The groove, crudely cut into the plastic, helps also.
Greg