ive been trying to install my pettit 3 inch downpipe all day and i cant get it to fit properly

i think the problem is a stud that stayed on the main cat, is this stud suposed to come out? ill post two pictures of the front of the stud and the back of the stud.
also the two big studs they provided to connect to dp- to the main cat dont fit the maincat holes.

i just need to know if this stud is supposed to come out, someone with experience help please, thanks.


by the way if i need to get rid of that stud, what can i use to remove it


stock 94 fd

 

I didn't have any problems installing my Pettit dp. It is easier to tie back the main cat so it isn't pushing against the tail end of the dp as you are trying to line it up on the turbo manifold. As for the studs to bolt up to the main cat...usually the studs stay in the cat and you just re-use your old nuts or buy new nuts. Coat everything down with high temp anti-seize when you do.

 

Both of mine came out but I have an aftermarket cat and they were bolts, not studs.

If putting the downpipe on would be easier with the stud off you could try penetrating oil.