Stock exhaust removal

[Slowlyvverot]

I just purchased a dynomax catback system for my '93 xlt. The problem I've run into is the removal of the spring-loaded bolts from the cat-to-muffler pipe. My truck has spent plenty of its life in northern winters so I soaked the bolts in penetrating lube on at least a dozen separate occasions. I've tried wrenching with all my might, to no avail. From the looks of it though, the bolts are tig-welded to the pipe, or something to that effect. I guess I'm going to have to cut the bolts?
My question is what exactly has everyone else done to get these bolts out and what size are they, since it looks like I will have to buy a new pair.
I've done some searching around but I haven't found the answer I'm looking for.

 

[Freshmeat]

If you have a torch, try heating them up. The nuts on the cat side are welded to the tabs to keep them from spinning in place. Are you putting the wrench/ratchet on the rear side of the bolts? The front side are the nuts and you'll get very limited movement out of them.

Other than that info, you just have to really put some force into it. Mine took all I could put in them and I'm 260# and roll falf ton drums on a daily basis, so it's going to take some work.

 

[Anime]

The bolts rust themselves to the flange on the catalytic converter, and give the appearance of being welded on...the same thing happens to the bolts on the Y-pipe in front of the converters, too.

Your best bet is probably a hacksaw or sawzall. Go to town in the middle of the bolt. The spring side will fall out and you can pull the exhaust, then pound out the nut/stud that's left in the flange with a hammer. Be careful, though, you don't want to mess up the flange on the converter.

For new bolts, go to any major auto parts store and get two of the HELP! brand exhaust bolts made for Fords. They'll have a spring and tabbed nut. They are the perfect size, and are very heavy duty.

 

[Slowlyvverot]

Thanks for the answers guys. Hopefully I can get this done today or tomorrow.