kfgk14,
thanks for the advice. I appreciate the voice of experience.
I'll have a look at the lift block you're referring to. I tow an enclosed trailer with the tipi poles on top right now with the truck and haven't had any problems with the suspension and I don't expect to go too extreme in my off road adventuring. But the reason I posted here was to garner advice from more experienced hands and yours is well taken.
I believe I've decided on replacing the bed of the truck with some aluminum cabinets for tools, supplies, etc and putting a capper on top of those. The inside will have a couple of storage drawers which can be pulled out from under what will be a bed. I'll carry and tent (I've given up on the idea of taking my tipi along) and cot with me so I can sleep outside the truck if the weather is nice. Given how tall the truck is now I'm a bit concerned that adding a bike to the top will make it too tall so I'm cogitating on that now.
Lots of work to do but I have time before launching the trip.
Thanks again for the advice.