I'm a mechanic, but not your mechanic. Those 4r70/75w are good transmissions. You said it has been well maintained, so unless there is some reason to doubt it... I would be more worried about the intake manifold/pipe under there. ACE transmission in Loveland is who I recommend. I had my 4r70w rebuilt with new tq converter at expert 4x4 in loveland for 1300 total two years ago. Has done fine since. $2900 is insane.