A friend of mine has a 2004 Chevy 3500 Passenger van with the 6.0L 4L80E auto transmission. The van has no tach or tranny temp gauge and he'd like both before he drags his camper around at highway speeds ... or faster :D.

1) Anyone know how to tap into what line for the tach signal (and what kind of tach to get)?

2) Same question as above, but instead if tach, put in "transmission temp" gauge.

Thanks for any help,