Just a few random thoughts about steering column etc.......

Most of the same era F-Series columns are pretty much identical to the E-Series---for some reason that fact seems almost like a state secret though. I'm curious if the Navigator etc aren't just minor cosmetic variations of that same general column design?

Clocksprings will be different depending if VSC or cruise control was part of the original build (or the chassis was pre-wired to accommodate that option.) The actual clockspring connector leading to the chassis wiring will physically be the same however Ford does change a particular circuits position on those connectors, seemingly to thwart compatibility between different years. The end result of this is no function because the required circuits aren't completed.

Having EVTM's from the affected years of donor vehicles in addition to the "new" vehicle go a long way towards demystifying which circuits need to be completed in order to establish or re-gain a function lost when different year or chassis parts physically fit but don't connect electrically.

Familiarizing oneself with the affected years EVTM's really will make this a lot more feasible.

I too am interested to see if this can be done--have just bought a '99 Volvo S80 sedan as a beater car it has SW radio controls---that's pretty easy to learn to love in short order!