lurk3r
+1y
I have an 82 B1800 and as far as I know the steering columns are exactly the same.
For mine, I undid the 2 bolts holding the Steering column up closest to the steering wheel, then the 4 bolts holding the cover over the bottom of the column to the floor, then undid the bolt you did to the steering gear box.
I also noticed it was very tight to get off, I covered it in WD-40 and let it soak, then used a pry bar between the bottom of the steering column shaft and the steering gear to pry it off the spline, that column was probably in there from standard so they can take a bit of wrenching to get them out.
Hope that helps