I didn't have this problem ... but my engine was "running on" just a tad when I shut it off, until I installed a diode on the wire that goes to the alternator from the ignition:
[img]http://www.alanhorvath.com/54chevy/chevypics/wiring_1.jpg[/img]


~~ Alan Horvath
1954 Chevy Pickup
Singing his praises in the
Passing Lane