Ok guys, here it is.
I have installed a diode out of an old alternator in the line right at the heater blower motor. Fixed it. It would appear that the heater motor indeed was generating enough to keep the ignition energized for a few seconds after turning the ignition switch off.
In case anyone else has this crop up, I used a diode from a 70's vintage Motorcraft alternator. (Please don't tell anyone it was a Ford) The diodes in this alternator are soldered to a plate and I was easily able to solder a short wire onto the end that came off the plate. The heater blower is wired with 1/4" spades, so I just used some crimp-on automotive connectors to make the connection. It does have to be installed in the right direction. One way you have no current to the motor, the other way you have no current comming back to the ignition.
Thanks again for all your help with this, and have a very merry Christmas!
Joe
