In 1962 Budd made a prototype called Budd XR400 powered by a 270 hp V8
engine. However the design was rejected by AMC. The caption on 1-st
photo (provided by Curt Hall) in Automotive Industries (July 1996)
states: "The 1963 XR-400 prototype for Rambler provided extra passenger
space behind the front seat. The fully operational XR-400 was a frequent
feature in parades."