<snip>
>According to the digitool which has a little LED
>showing when the throttle position switch (TPS) is
>activated, things are operating where they should.
>Just the barest touch of the pedal (very barest) turns
>the light off.
</snip>

Ah, I didn't know the digitool monitored that (I don't have one, but
probably should... seems like a great tool!). Sounds like your switch is
working OK, if it is turning off at the barest touch (as long as it isn't
coming *on* before the throttle is fully closed, then it's not the problem).

I suggested it because I've BTDT with the throttle switch, very similar
symptom... but it sounds like your problem lurks elsewhere. :-(