The fronts are for the RC10T truck bulkhead and nose plate, so are the same as the 91 worlds by RPM.
The rears I believe can be used for the narrow (cut) chassis or the uncut with longer drive shafts.
When I got them they were fitted to the uncut chassis with standard rear hangers. I have just tried them on the RPM 91 Worlds rear hangers and they fit. I don't know if they would need slight dremelling on the edge where they meet the chassis edge, but wouldn't of thought anything major if any.
Hope that helps....
