@Husker, that is great information. #3648 was completely restored in 1986 when I bought it. It was originally Red, and on the backside of my firewall cover, it is written in yellow "Red Sled". I have a great rear luggage tub (tray) if you would ever want to trade or sell your tub. Now I just need to find the person that bought #3648 after it was parted out. Do you still have the #3648 351C?
I will share another interesting clue, is my rear shock brace is what I was told is one of a kind and that it was hand made by the previous owner of #3648, see picture