The Corson looks nose long because it is missing the 3" in the rear quarter to offset the long front nose section. The oem 512 had an additional 3" in the rear quarter area for the longitudinal engine setup. If you take a side shot of a Corson and add in the 3" in the rear, it makes a huge difference in the overall look. I also believe the Corson nose is a bit longer than oem but not much though.
$6k for a beat up Corson is still a pretty good deal since the good ones go for quite a bit more. The convertible was always a very good looking car. Randy Corson had a convertible himself and drove it regularly. A more rare find as well as I don't know for sure, but I don't think he made many of the convertibles. Most were the coupes.
If the rest of the car is in good shape and it is fiberglass repairs, $6k isn't bad. If the frame is pooched as it might be from the notes above, then you buy for the panels and find a new frame and reinforce it properly. Archie's kit works or there are also other options like Yarmouth Fiero's final design....
[This message has been edited by 355Fiero (edited 01-22-2014).]