Went to advanced and they showed 11 or 13 bolt pattern gaskets. I assumed rear end was always in car but maybe not? My car is a 1980 oldsmobile cutlass supreme that came with the 260 CID. Thanks for any insight.

 

My rear end has a 10 bolt cover

 

You should be able to find a gasket for that. But you don't have to use a gasket. You could use RTV, permatex gasket maker etc.

 

Your rear end should be a 7.5".

Tell the dummy at the parts counter, the gasket is Part No. RDS 55072

 

Thanks for the help y'all...it's 2.23 rear end that came in car as I have the build sheet