I think I have you all beat at 6'3" and 280#.
I have a Contemporary and had sold the seats. You need to get down on the floor but get the seat mounted/anchored to the frame, rather than to fiberglass. My seats were fabricated as was the entire interior by Steve Bell in Laytonsville, MD.
I had the header pipe closest to the driver moved to a "forward" position which gave me about 3" in the foot box which is HUGE for someone with size 14 shoes. In addition, moving the 3rd to 4th (?) shift rod on the transmission (toploader) gave me about 3"-4" at the thigh. It used to run along the side of the transmission but now goes over the top. The steering column was moved to the right and now I am in the middle of the windshield rather than looking over it. Nick Acton from Acton Customs did the interior structural mods.
I love driving the car now and do not hesitate to put 150-250 miles on it in a weekend. I put over 4000 miles on it in 7 months. I drive it. SAY IT!.
