Sounds like a real peach.
Well.. un-welding consist of cutting and nothing more. If it was brazed you could heat it up and loosen and lose it that way but its welded so there is not un-doing it. Just cutting and cleaning up the ends. Maybe grinding down some of the weld if need be.
My stuffs been welded, cut, re-welded and then cut and re-welded some more It never cost more than 40 to get it welded, and was usually 20.
I have slip fits and clamps on the headers and welded everywhere else to prevent rattle or sag or any type of movement. When I have to take the exaust down for other work I'll just cut it and have it re-welded again. A sawzall works just fine for cutting and depends on who's running the plasma cutter will do a much better cut. I have a nice grinder so I'd use a cutting wheel. Is your exaust dumped right now or run out?

 

Sadly it is LT's to dual cat to an x-pipe to 2 bullets over the axle.....but it hangs REALLLLLY low and is fully welded so live & learn I reckon. If I can find a good catback I may be in style since I just found a brand new catted y-pipe for a great price.

 

I thought someone in your area had a catback for sale. Used but I thought it was a borla. A month or two back or so. Otherwise new cb's are anywhere from 350-750

 

I would take a Borla

I am working on a used GMMG but the guy isn't going to get it off his car till he gets his true duals bought/installed.......so if I could find something local (faster) that didn't suck, I would be thrilled.