Welcome
Dudecw
Do you still have the V6? More photos are always welcome.
I would get a factory manual for specific items. Here is a link to the New 6066 GMC site.
http://6066gmcclub.com/forum/index.php?
Here is some info I got from one of the members there awhile back about torsion adjustment.
Henry, this is Lewis Matkin. As regarding the height of your torsion
suspension, I have possessed and driven Chrysler products most of my adult
life and know something of ride height on torsion suspensions. If you have
done your adjustments per what the GMC manual says, more than likely one bar
is a little weaker than the other. The only option I am aware of is the h/d
option that was available for about $5. from the factory. I remember my dad
telling me that they ordered all their trucks with the h/d option and leaf
rear springs. That was a regular production option which was available
during the 1960-1962 year models. To bring the heigth of the vehicle equal
on the front, instead of measuring the control arms like the manual says,
you will have to measure frame heigth. Take your measurements in two
places: at the frame just behind the bumper, and at the bottom side of the
frame at the front cab mount. Make them equal. That should equal out the
height of the truck. There is no stiffer/softer torsion bars side against
side that I know anything about Henry. I hope that I have shed some light
on your problem.