Need help with steering column swap

[Denise 20352]

  Im swapping an early 70s (exact year unknown) tilt/tele column into a 1976 commercial chassis with fixed steering wheel. The columns look identical, except for some of the connectors.

  The first thing that I noticed is that the ignition switch is different (not the keylock, the actual switch).  Can I swap these, or is something bizarre going to happen when I undo those little allen-head screws?  It looks like maybe you can loosen them to adjust the switch, but Ive never removed one.  Is the rod likely to fit?

   Next thing, there is the big, long connector.  They look identical.  Is it likely that I can just plug this in, or are there differences?

   Then there is the neutral start switch and parking brake valve assembly.  There are three pairs of electrical connectors (spades) on the fixed-wheel column, but only one on the tilt column.  I only pulled a connector off of one of them, which I assumed was neutral start, and I dont think that anything was plugged into the other two.  What are those for?

Thanks for any advice, input or dumb looks.  I can post pictures if necessary.

-denise