Based on the guages, sounds, and performance of the car, nothing is faulty. I'll dig out my obd2 reader today and see what active code is pulling that light on.

-edit-
P0102 (MAF/VAF A Circuit Low Input)
P0122 (TPS/Pedal Position Sensor A Circuit Low Input)

I guess I could assume that both my MAF and TPS are going bad by this, but what are the odds of simultaneous failure like that?

 

or connectors are not happy. have a look inside em and see if they is not getting good connection. sometimes the metal loses its springy and needs re bent or replaced.

 

Sprayed and brushed out the sockets, messed with the plugs to get more contact down on them... still 'CHECK GAGES'. Think the TPS and MAF might actually be on their way out.

-edit-
P0122 is the only stored and active code now, for the TPS. Might be bad connections, but I'm more inclined to believe the TPS is bad at this point.

-edit-
Confirmed bad TPS. Did pin-out test, resting voltage (closed TB) fluctuates randomly, high-idle on startup without warning symptoms starting to exist now. Going to pick one up from O'Reilly's tomorrow.

 

Alright, sorry about the double posting, I just don't know if 3+ edits on a single post is frowned upon.

Anyways. New borg warner TPS installed, most of my new symptoms are gone now, with the addition of one big benefit: smooth throttle now.
Car used to idle a little funky, converter would randomly start to engage, like the ERPM's would be in constant fluctuation. Totally smooth at idle now, and instant throttle response with no more funky-ness.

I still have a 'CHECK GAGES' indicator, but I can't pull any codes from the computer, both with my cheap-o Amazon OBD2 reader, and a Bosch $450 (proper) setup. No stored or active codes at all.
-Oil pressure indicator is just below half at idle (around 750rpm), then upwards of 3/4 or higher under WOT, no odd noises.
-Battery voltage indicator is always high on my car, due to the 150a alternator; I do mean a true 150a, with 150a at idle. Hasn't had any problems yet, also installed a 950 cold crank amp battery when I replaced alternator (it's around 933 or 935 actual I think, might be higher, haven't tested since I bought it).
-Temp guage never usually over 160F, though I know how accurate that can be. Hasn't been running hot though, coolant is fine, always full.
-Oil is fine, level is good as is color.
-Transmission fluid full, good color (should be, less than 2k miles on new transmission and converter(s))
-Fuel gauge still working properly, don't have any real problems with filling, other than it belching fumes a lot when I get to filling about the last gallon in the tank, I think Craby mentioned this could be evap system related, I forget.
-Coolant level sensor definitely dead, constantly either a dim light, or full brightness light, despite full level. No idea what to do on that one, other than maybe some electrical tape or removing the indicator light bulb from the cluster entirely.

All indicators say good to go, but I've still got that dummy light. Blurhgh-grumble-grumble

 

only thing that sticks out is the coolant light being on, although its not a gauge it may be setting the check gauges light. maybe try unplugging the sensor at the radiator or it needs a new one.

 

I'll get to un-plugging it this week, see if it clears the dummy indicator.

That being said, took the car out to Jacksonville from Tallahassee this weekend, still drives like a dream now. I do have a bit of an issue, in that the fuel pump makes a consistent whine after ~2 hours @ 80mph on the road trips. Either that's normal (not the normal semi-quiet whine when your first roll the key over and it's building pressure, very notable even over the car running both inside and out), or the pump is on it's way out the door now.

 

oh boy, pump is not happy,,, how old is it

 

Probably as old as the rest of the stuff that's never been replaced in the car. It's only got 76k now (thanks to me, from the 74k it had before), so it would be a very conservative bet to say that it's the original fuel pump.
When it's out for drives that are less than ~2 hours long, it seems to run fine without audible complaints being heard, haha. I'll probably just get a new fuel pump here soon to be on the safe side. That sucks though, because that means the tank has to get dropped out, and I don't think I'm able to do that in my driveway (safely, which means more money out of my (increasingly) burnt wallet.

Also got my one tacky addition to the car, courtesy of eBay.

 

could do the hatch to change it

 

The hatch??