@Lwiddis thank you.
@opnspaces thank you for the welcome and also thank you for posting the pictures. I went back to the original post and tried it myself to learn how to do it. But I still appreciate your gesture.
I'll definitely go more on an angle to lessen the problem.
I just checked underneath and I'm discovering some things. I bought the rig from a dealer who accepted it as a trade-in from the original owner. I never got to talk to the owner.
But it's clear that the owner towed something because the rig came with the hitch and he bought the V10.
Actually looking underneath showed me several interesting things:
1. it already has castor wheels. See picture below. I haven't had a reason to look behind the rear skirt and they are invisible looking directly at the rear because of the skirt. That's nice—one less thing to install.
2. it does have leaf springs and they are mounted atop the axle. Thus, it appears I can put a spacer there and an extra spring.
Peering underneath showed me the castor wheels:
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So, given that I still want extra height, it seems the new short list in rough order of preference is:
1. install a spacer
2. install another leaf spring
3. install a rear stabilizer from Hellwig
4. install new, stronger shocks (but only if necessary)
5. install air bags
6. install front stabilizer
7. install a front-and-rear lift kit
It seems to me doing 1 + 2 + 3 get me really close to what I want. If not, I replace the shocks and add the air bags and front stabilizer. It seems that the full lift kit (with its high cost) isn't necessary at all.
Did I miss anything?
It seems likely this will give the rear 3 extra inches. The rear will be higher than the front but that shouldn't cause a problem, correct?