I have a 71 that i had gray phosphate coated. PM me and i will send a picture. Pay for coating and shipping and it's yours. Gary
I'm not a 1971 GS expert, but I'm pretty sure there was only one alt arm for that ap whether it had AC or not. You may already have the right arm. If Gary's doesn't work for you, I have an NOS 1971-72 arm listed in the Parts for Sale here. http://www.v8buick.com/index.php?threads/nos-1971-75-gs-455-alternator-bracket.353041/
Frank, There were several different braces for the big block cars, but, you are correct in that they were non- A/c or A/c specific like the small blocks are. Matt