Yeah I don't how the hell those holes got there! Anyway, replaced that, Napa had the part for $25 easy fix... Pushed it hard on the trails yesterday and it's only reaching near the red zone (about 250 degrees) under the most extreme climbs. Had to kick the heat on again from time to time. New res tank seemed to help some but not completely. The radiator cap is sealed tight so that's not the issue. All the hoses look okay so that's good news too. What I think it is actually is the engine fan clutch is bad. Correct me if I'm wrong, but when the engine gets to normal operating temp and you shut the engine off, you shouldn't be able to spin the fan freely at that point with one finger. There should be some tension there right? Anyway, going to replace that and see what happens. A full system flush probably wouldn't be a bad idea either.
Also, was reading this today and it says the off-road package (which I'm pretty sure I have due to the skid plates, Dana 44 rear, etc.) also included a bigger radiator. Can anyone verify this?
"The optional 4x4 Off-Road Package included high-pressure gas shocks, front tow hooks, a heavy-duty radiator, and front skidplates. There was also an available Trac-Lok rear diff for the 4.0L (if the truck had the fullsize spare)."
http://www.fourwheeler.com/project-vehicles/154-0610-jeep-comanche-mj/