I bought a 70 Challenger convertible in 1982 at NAS Millington TN. I purchased the car from a young Marine who was shipping out. The car had a 318 in it but I believe from the rear end and Radiator it was originally a 6cyl. I have replaced the 318 with a 340 and gone with a 8 3/4 over the 8 1/4 I am in the process of restoring. I have owned this car for a long time and it is not for sale just wondering what it is worth.