where can i get exhaust studs??

Good luck finding those,I tried a while back and none of the part`s stores around me had them.

I just used four Grade 5......7/16" x 3" long bolts with 7/16" washers.

Works just as good and easier to find/buy.

A local exhaust shop might have them or you could buy 7/16" threaded rod at a fastener supply store and cut it,but regular bolt`s work just as good.
 
My local Lowes used to carry them in section where all the botls and nuts are., they had a selection of studs in 7/16" - 14 along with the correct, flange nuts. I used then to replace all of the rusted hardware on my mac exhaust. pretty sure I used the 2" studs.

I went last week and they where no longer there when I was serching for a set for my other car. Maybe it was just that store though, can;t hurt to check?