I did this very job about 2 months ago, on my '96 GL with the 3.0L Vulcan engine.
Here's the hardest part of the whole job; get past this and the rest is gravy.
To disconnect the exhaust pipe from the rear exhaust manifold, you'll need a 15mm combination wrench, a short 15mm socket and a 3/8 drive and swivel
For the nut nearest the driver's side, I was just able to break it loose from above, with the wrench. Then, working from underneath, I was able to FINALLY get it off, working it s-l-o-w-l-y down the stud with the wrench. Plan on about 2 or 3 hours for this little job!
The other nut I was able to get onto with the 15mm socket and swivel. You might have to run one wrap of tape around the swivel, to get it to stay up while you try and work it over the stud and onto the nut. I had a pair of long 3/8" extensions on my ratchet, BTW. That whole mess wanted to do anything other than break the nut loose from the stud - I had to hold it firmly against the side of the exhaust pipe where it went up, in order to transfer any torque to the nut itself.
I'll go out and look at my car, kind of jog my memory for what all else. But this was the absolute, very worst of it.
Edit #1: You might be able to loosen the closest pan bolts and push your gasket back into place, for a temporary repair. When I did mine, I used the gasket from Ford, which is (now) a hard plastic frame that holds the sealing material. Keeps this sort of thing from happening.
Edit #2: Plan on a full weekend, from Friday night to Sunday night. I just drained and changed my oil; I didn't change the filter since the filter and oil weren't all that old.
You'll need to remove the starter motor, too. But getting the exhaust Y-pipe out of the way is the heavy hitter. I didn't remove mine completely - I just worked around it after it was down far enough to be out of the way.