Engine: 1998-2001 360ci (5.9L) Magnum V8 245hp(standard), 250hp(Sport package)
Rep Power: 0
One important thing...
Its sounds like you have an electrical guage?
When you add that manifold/sender to the pressure line which is the tranny temp going into your cooler, you may have to run a ground strap over to the body from the manifold/sender body.
I found when i installed mine the plastic end tanks on my radiator didn't allow enough current for accurate readings.