Steering Column Questions

In the finishing stages of my power steering swap using a 491 casting three bolt box that was on a junk frame i had[77], while refurbishing and reusing my original column[1972]. My question is what coupler kit should i order. Seems a siily question, but i'd hate like h**l to order the wrong one. The box was on the frame when i aquired it, so i can't say for sure if it is late model or older. Any thoughts on this would be most appreciated.
mike

 

originally from the factory, the 77 had a bell coupler
the 74 manual box had a bell coupler also
the P/S bell coupler is a larger diam spline shaft where it slides on to the box
so you need a bell coupler (and the internals) for a 74 and later CJ with power steering
you might also need the lower shaft for power steering as well, the shaft that goes from the box to the u-joint ????
they show a diiferent number for power steering, but the internals inside the coupler are the same
maybe one is shorter than the other ????
I don't recall the differences on the shaft

 

here's a quick pic