I know this is an old thread but I'm hoping you'll still answer joe. I see you said the brackets interchange from '68-'76. I have a '77 Cutlass 442 that I'm swapping a 455 into. The car currently has a 350 in it. Will the brackets swap from the '77 350 onto my 455? I have two sets of brackets for the 455 but both are for A/C which my car does not have so I obviously don't plan on using.

 

I moved your post here, where it will probably get more visibility.

1977 was the first year that the BBO was no longer offered. Most of the dual-compatible brackets were still used, but it depends. Photos of your 350 brackets would help. Are you retaining the driver's side alternator or moving to the non-A/C passenger side brackets?

Since it is not affected by the deck height differences, the PS pump brackets are the same for both BBO and SBO. As always, be sure you properly install the spacers between the PS pump bracket and the block, or it will never align. We'll need to see the alternator brackets to figure out if they are dual-compatible or SBO only.

 

Joe, yes that's why I was curious as I knew '76 was the last year for the 455. I could try to get some pictures but it may be tough as they are still in the car on the 350. As the car sits, the alternator is on the passenger side. My hope is to be able to use all of the brackets and pulleys from the 350 to install on the 455 in the same relative locations as how they are on the 350. Are there any tell tale signs I can look for that would tell me if they're interchangeable?