Any 71-2 Skylark with a 350 and PS, you can transfer the brkts to your 455. Here is an article on our site showing the differences: http://www.buickperformance.com/ps.htm
i have the aluminum bracket and the metal ones that mount on the pump from a 71 skylark $45 plus shipping let me know Greg
I am currently using a 350 bracket set up (steel), but I have to use spacers to line it up properly. Am wanting to do it right with one of the aluminum brackets.