i have a 85 cutlass i lost my Exhaust Flange Gasket (donut) out my exhaust. i want to autozone n they give me one that was a 2 3/8" inner diameter but when i put on my exhaust pipe it didnt bolt all the when up and the donut didnt went in the pipe all the way . so can anyone help me with this problem ,i trying to find the right size one to get, i know it have to be a smaller size to get. but just looking for the right size now to tell them.