A little lighting help please

[ChemMan]

I just realized that the trunk lens assembly has been full of water for who knows how long, and all the bulbs and sockets have been corroded badly. I managed to salvage everything except the little metal band the goes inside the back-up light socket, they were so corroded that they crumbled into pieces when I removed them. Can I get replacements for those metal pieces, or do I have to replace the socket entirely? On that note, what bulbs do the back-up lamps require? Alldatadiy.com gives the part number as 3156, but the old bulbs where the bayonet style and 3156 is a plastic plug in style.

1997 Bonneville SE

Thanks.

[Bassasasin]

Guess I would go to a junk yard.. get parts.. other GM vehicles may have similar parts... Not sure if Canadian parts assemblies are a bit different.

Bass