welcome, and that like you said, is a contraption. Not a mechanic, but that looks like a personal mod and should be checked out and changed to correctly read your temp. good luck and post back the answer.
Nothing to it but to do it.
SIMPLE AS THAT.
'04 TJ RUBICON, 4.0l auto
2"BDS coils, Rubicon express shocks, 33/12.50/15 Dick Cepek Mud Country tires yellowed out, on Black steel D's.