I'm sorry Mike I've seen a number of them thru the years and owned 2 commando 66 Darts. You know back in the day if the factory ran out of something they used what they had. I've seen Chevy rear axles in Pontiacs and vice versa. I seen all kinds of stuff back then on new cars that people say they never built. I even seen a 70 Cuda with the billboard decals with one side said 340 and the other side 383. lol These were all new back then. My uncle had a 69 R?T Charger and blew the Transmission but they already started on the 70 model year so they put his car back on the line and replaced the trans. and put a extra one in the trunk. Had one guy that used to come in with his trunk full of ring and pinions $20.00 a set right from Chrysler, me and my friends always had quite a few laying around. The orignal owner of Camcraft was one of our customers. He did all of Richard Petty's stuff back then and would just come in with a camshaft and say try this one out. I worked right in Hamtramck (well 6 houses away).