@bucket, I’m confused too. Or think I am.
Is burbzilla “not” the OPs truck and the black one is? Think that’s what I got out of this recent post.
At this point, OPs priorities or wants seem to be in conflict with his wallet and real world conditions.
Short answer, 40s won’t destroy axles (at least quickly) if it’s just a show truck. No bumper cars, lol, no hooking up a 40 mph burnout on a log or dry pavement.
But if you want to use the truck, and actually put any real torque on those 40s or whatever, stock half ton axles will be in the scrap heap fairly quick.