If we go back to the question "does a XLS body fit a Procat?" then yes as long as you change the lower chassis plate. It all depends on what you want?
If you want an original XLS using a Procat then I wouldnt bother

However if you're like me and prefer the XLS body and you want a nice vintage club racer and are not to bothered what the Schumacher experts say (Which I m one) then do it
This is my runner Procat..