I have a lot of S gauge heavyweight passenger cars, including two sets in PRR livery. One PRR set is American Flyer by Lionel, the other set is American Models. These cars scale to 72' at 1/64th scale, they are about 12" long. I also have a lot of original Gilbert S gauge HW passenger cars but they were never made in PRR livery. I imagine that O gauge trucks can be installed although these cars were designed and manufactured long after the original Gilbert 1/64 scale O gauge passenger cars were last made in 1941.
The tightest radius these passenger cars will run on is 18", that would be O-36. Even if the steps on the chassis are cut off these cars will not run on standard O gauge track (O-31.)
