x2 on too cold a fluid .
add a gauge in the pan AND 2nd sender in hot line out from trans to cooler . then install toggle switch for the sender wires feeding the gauge . this will let you know how hot you are working the trans and for the reg driving just the pan temp will be fine . . . only if you like to know lots of info do it this way .
also they do make automatic thermo switches for fluid control that you can plumb inline so it flows stock and when it gets to a specific point ( temp range you ordered ) it will flip the flow and run to the cooler . then when cooled down back to normal .
https://www.summitracing.com/search/...9%2B4294882595
and yes to good temp range is 180* .
i remember my old c3500 with 4l80-e would not lockup in 4th untill the engine coolant was atleast 140* warm . so even gm knows to cold is not good .