A few months ago I broke the rusted bolts on the Y pipe ring while removing it from my parts vehicle. I tried beating what was left over out with a hammer, then a sledge. I couldn't tell whether they were pressed in or threaded. Since my buddy needed the Y pipe I checked the forum and couldn't find an answer.

Last night I was helping with ball joints and since we had the rented tool I tried it on those bolts. They pop out and are not threaded to the ring.

Just posting in case someone else has the same issue.

 

Yep, that works and you can also just heat them up with a torch and tap them out (assuming you have access to one). That's what my exhaust guy did when he saw I had it held together with a cheap pair of vice grips.
Amusingly enough, that's also what's holding my y-pipe to both of my exhaust manifolds right now. Two pairs on the passengers side and one pair on the drivers side.

 

Hahahahahaha that's amazing.

I'll do you almost better. When I suspected the were studs and tried to beat them out I went in the garage and found my propane cylinder was empty so I got a can of wd40 and a lighter. It got really hot!!!!