4406bbl thanks for checking on the radiator inlet and outlet port sizes.

I did confirm the gage is accurate with a second gage and laser temp gun. So I am going to try less timing, going from 15 initial to 8 initial and a step richer jetting, to see if temp drops. Motor is stock bore motor home, at 8:1 comp so it probably doesn't need all that ignition. If this does nothing, then rad will get pulled and tested, its a used unit I have had for near 20 years hanging around in my parts collection.

Mike