I like your car, back in the 70's I had a '67 RS/SS 350, 4spd, 12 bolt posi. I pulled the motor and put in a 302, I didn't care for that, so pulled it and put in a 454 that I had built for my other '67 Camaro. At some time I put the 350 in a Vega panel I had.
I sold my '67 RS/SS to buy a '70 RT/SE Challenger 383 Mag/727b posi.

Pat