The Centurion was basically a four door Bronco. Centurion vehicles first caught my attention with their Econoline van based "Vanup" drw conversion van/dually pickup conversion. It sounds like a crazy idea but it was an awesome long distance tow rig. The Centurion 4dr Bronco (that they couldn't call a Bronco) was actually done by Ford just prior to the end of the original Bronco in 1977. The engineering prototypes for 2dr and 4dr were referred to as Shorthorn and longhorn. I don't recall the reason Ford passed on the 4dr, but I suspect that rollover concerns with the extra weight and high CG were part of the decision.