JIM72VT,
I really appreciate your response and the link. Unfortunately the cars I have appear to be a bit different. These have only 2 screws on the chassis instead of the four. When I tried removing those I did not feel a difference between the body and the chassis. They may well be what's holding the body to the chassis, but I didn't want to apply any more force than I already have for fear of breaking something. I'm sure it's something simple, but until I understand the correct process I didn't want to over tax anything.
But, thanks again for the effort.
Barry