I had horrific "wobble" from 35-50 mph

a simple Dual Stabilizer killed the wobble permanantly. sorry to hear you're having such issues. are you running a single or dual setup? single just doesn't cut it IMO.

btw, I've experienced death wobble before on a a TTB 1993 Bronco with 35" tires as well. It's not necessarily a design error. It's more just a fact of life you'll have to live with when running huge tires. BTW, I solved the issue on that vehicle as well with dual stabilizers