Oh, it sucks, BIG TIME.
AAAAAAAAAAND, that interior panel, is covered with sealer/butyl/etc.
Watching you jump down that flight of stairs over the edge of the garden at your old place when I was there for dinner shows me you have about the right physical ability to get into this car to do it. LOL.
I've taken the belt off from underneath, but that was just to change the blower, so I can't verify that you can swap the belt completely, but you can get the tension off and the belt off the supercharger pulley without taking all that interior stuff off.
Also, I would recommend putting that car on a drive-on hoist to do any underneath stuff, to jack one up at work, I had to take the front wheels off an ultra-low-profile racing floor jack to get it FLAT on the ground to jack it up.
Once that interior trim panel is off, it's not a HORRIFIC job, to be honest, but that trim panel is no fun to take off, especially when you're my size in a 250,000 dollar car.