1969 Dodge Dart Swinger 340 Sold at Mecum today for $40,000

That's a lot of money but I sold a nice 68 dart 6 cyl car to a friend. He installed 318, new interior, paint, etc. Does all the paint and body along with his Dad. Told me that he ended up well over 30k. I just don't know if one could do a quality job on a bona fide swinger 340 for 40k.