Today with a little research along with the "Torsion Bar 401" thread on GMFullSize.com website, I found some thing to take the mystery out of torsion bar swapping.
Your original torsion bars are listed in the glovebox, My 2000 was 6XL and 7XL. This is good to know because most factory torsion bars loose their tags after a while on the road.
The torsion bar 401 thread has all the part numbers and torque ratings for the bars.
Today I found out that the torsion bars have the last 3 numbers of the part number stamped in the end of them.
No more mystery about GM torsion bars, you can look at the numbers, look at the chart and find the torque rating.
I had snagged some torsion bars from a GMT 400 pickup at the wrecking yard last year. I was going to use them in my 2000 Suburban since it has XL torsion bars in it.
I found out through my research that the bars I snagged are GG bars, the same as the ones in my 1993 light duty K2500 rated at 6707.
My 1993 Suburban has GH bars rated at 7161.
The difference in weight between just the engines alone (about 50lbs) satisfies me that I can run the GG bars in the 2000 and have some acceptable lift and possibly use the stock GM keys.
Armed with the Torsion Bar 401 info and the numbers in the glove box you can go to the wrecking yard or buy used torsion bars and not buy something that will not improve your ride height or weight capacity.
I hope this helps everyone, because personally I would rather install a heavier bar than crank the bars.
I also bought a set of Ford torsion bar keys yesterday for about 15 bucks from pick a part.
The passenger side came out easy, but I had to find a little jack to unload the drivers side a bit to get the threaded rocker out of the crossmember to remove the key.
Read my above post to see what I found out about Ford torsion bars.