mine had the death wobbles a few years back and i mean death wobbles! when it did it you would think you were about to die! the steering wheel would almost be ripped out of my hands. it felt like it was going lock to lock 5 times a second. violent shaking is the best way to describe it. it only did it going around a sweeping right hand corner at about 50-60km/hr. there is a corner in weipa where it would do it everytime. i changed the steering damper, nothing. wheel balance, nope. wheel rotation, nope. shocks were good. wheel alignment, good. all front end bearings, good. tried everything, no difference. was running out of options when i found the rubber bushings that hold the sway bar to the chassis had a small amount of play. in my desparation i took them out and contact cemented in a piece of 3mm rubber to pack them out to give a tight fit on the sway bar. BAM! instantly gone. never had a problem since.
it's scary how something like that can have such a dramatic affect on handling. it was dangerous and downright scary!
i haven't done the radical suspension mods that you have done but it might pay to check all your sway bar bushes.