Yet another running hot issue

Hey everyone. I've been searching and googling but have yet to find the cure for my running hot issues.
Initially swapped in a new gauge cluster and discovered that I was running just below red line. Started swapping parts to no avail. All that was swapped includes: radiator, thermostat, water pump, hoses, fan clutch.
All of this yielded no change. At this point I picked up an IR heat meter, and discovered outer temps were within nominal ranges. Swapped the temp switch at the valve cover and temps dropped, but still running high, approx 220 at the gauge (cheap IR meter pooped itself at this point).
Took it for a test drive and while driving gauge cluster temps dropped to just above 210, and raised when slowing or stopped. This points to bad fan clutch (which I just replaced), so I changed out the coolant temp switch at the Tstat housing, but again, no change.
I am at a loss and welcome any advice. All parts have been changed, but can't seem to get this beast down to normal operating temps.

Zj fan clutch, good shroud, distilled water only, 185 t stat from dealer, burped correctly. Start there.

do the gauge readings match the IR gun? The factory gauges are notoriously inaccurate-- you might be chasing a ghost at this point.

Get the radiator cap tested (many are bad off the shelf) and look for an exhaust leak (crack, gasket or flange donut leak) blowing hot exhaust on the block.

IS the E-fan working?

What year is it?

Is the new clutch bad? Try a ZJ clutch!!

Zj clutch, holes in thermostat, new exh manifold cured mine.
For $100 or so from 1a auto, its worth replacing the stocker.

Thanks for the responses. To answer the questions, rad cap was replaced with a "pressure release" cap, IR gun is crap (pooped itself, and will be replaced tomorrow), E-fan is on a manual switch (but doesn't seem to affect anything, will probably be replacing soon, as well). Can't run straight distilled water, as it occasionally freezes here in NC.
I have also been working on clearing up some serious engine build up, which I thought might have been contributing, but no joy there. I have picked up a Stant Tstat, which will go in tomorrow, just to rule all the usual suspects out. Have also, verified that I'm not seeing any coolant leaks, etc. Getting to the point of wondering about the possibility of head gasket issues, even tho I have no symptoms (just running out of crap to replace).
Definitely appreciate all the input, and will continue to provide updates as I find them.

Well, engine build up seems to be better, but didn't get a good seal on the oil pan, so spent today correcting that. Will re-adress tomorrow, hoping towards resolution. And since I seem to keep forgetting to answer, it's a 94.