I have a 50 Buick 2 door sedanet. I want to do a frame change. I am told the wh is 121.5 (seems like 125) however, I want to use a 70 to 76 Buick Le Sabre, Electra or Centurion doner(124 wb) with 455. I was also told a 63 Rivera would be good also. I plan to cut the floor pans out of each car and swap. What do you think? Has any body done one of these? Thanks