tried pulling the steering column, What I do see is that the lower section of the steering shaft and coupler has two u-joints with a double center yoke (C5TZ-3814-B) in between them.
A clamp yoke (D2HZ-3814-A) attaches to the lower steering shaft & coupler (where the lower u-joint is located), then attaches to the input shaft of the steering gearbox using a pinch bolt, two washers and a nut, the shaft & coupler won't fit through the base plate[hole in floor.....one more obstacle. will take a "saws all" to the floor and enlarge opening, unless other options are available

 

finally replaced lower bearing, now to re-installl steering column in truck.
should replace u-bolts, but i only received one from Miller Obsolete parts, not two as required

 

replaced lower bearing and returned column into the truck; seems to be OK, hope to take it for a test drive tomorrow.