I think until you address approach and departure angles, custome bumpers, moving the wheelbase, etc. The Expy is never going to a Bronco, K5, etc.
Rockwell and link it on 46's.. approach and departure less of an issue, but shy of that.....
Ditch the bumpers, move front axle forward 6", have the tube bumper wrap right under grille. Link it.
Ditch the rear bumper, slide that axle back 6", whack off the last of the wheelwell, the part behind the rear tire... and run a tube work back there as well,
Make that 18" for rear tire... Oh wait, then you have an Excursion wheelbase....
They weren't designed to be the Bronco. They were Fords Suburban getter, which I feel was in part inspired by the succes of the Centurion Bronco..