I am not trying to talk you out of buying this harness, but they make harnesses for what you plan to do, they are called Trapeze harnesses and they are made for mast hoisting during racing and repair.

Baltasar,

This is what you want. http://www.backcountry.com/outdoorgear/Black-Diamond-Bosuns-Chair/BLD0965M.html

The goal is to get the weight off your harness. Any cheap harness and this chair will do the trick.

This should definitely do the trick for you then. Big wall harnesses are meant for long use so that would be the way to go and it looks like this harness has quite a lot of padding on it even for a big wall harness.

I used the 22"-24" size range from the sizing chart in a circle formula to get a diameter of roughly 7.3". Sorry not hands on measuring, but hope that helps.

No, these are all climbing harnesses with the loop in the front. However, Metolius harnesses have full-strength haul loops, so you could use it in a pinch. I wouldn't recommend it.

Unfortunately, Metolius is not currently making a XL in the Waldo, but Angus is right the Waldo has a waist of LG 35-42"

Though not in stock, there is indeed an XL version of the Waldo. The waist size on that goes up to 42 inches, which is pretty hefty, so you should be fine.

This harness is intended for long, long climbs. That being said, the extra loop is just for extra organization of gear, ropes, etc while up on a wall for an entire day. That area of a harness can get a little crowded, ya know?