Reading through what has been written those temps are too low & you need to be running @ about 190*F.
If this engine was rebuilt & as "new" the block would not be full of sediment, but it may be worth checking.
One thing missed & not asked is are you losing coolant? No then you are not boiling & if you are not boiling you are not overheating.
Can you squeeze either of the radiator hoses when engine is hot & they feel tight? If so the radiator cap is fine & holding pressure.
Another thing is when you turn off the engine there will always be a heat spike, that is normal.
Do not continually fill the radiator....topup to about 1/2" over the top of the tubes, only about 1/4 of top tank.
With todays grades of fuel most Jeeps are running retarded, if set by the book/timing marks.
Try advancing timing @ least 5* extra....even up to 8* & check for pinging [load in top gear going up a hill] if none you will be running cooler plus getting more power & improved fuel economy to boot.
You can, as I & some others do, adjust timing to optimum using a vacuum gauge.
John GIBBINS [EX A.R.A., A.Res & RAAFSR]....ASE Master Truck & Auto Technician