I was having a T/S problem and I posted about it quite awhile back, so far back it fell off the boards. Anyway, here is a follow up with a twist, at least I think so anyways....
I found a "TSB" for this problem with the help from the Thomas Dist. here in Iowa.
The TSB talks about the turn signal cancel pin being in the incorrect position. It's supposed to be in between the 0ne and Five o'clock position. The one on this bus was at the Nine o'clock position with the T/S switch.
Not having the new horn contact/cancel pin assembly (RGT SK000278). I disconnected the steering shaft, slid the shaft off of the splines and rotated the upper steering column 180 degrees. That put the cancel pin at the Three o'clock position. Reassembled and went for a drive around the lot playing NASCAR and it seems we have a winner.