Well,
I took out the dash and verified that the connections were clean and tight.
Started the car up and seemed fine. Then, to put more load on the battery, I turned on the air compressor and the gages were "acting up" again.

I also verified the cleanliness and tightness of the battery connections ...

I also have a 93 ssei and am having dash problems as well.
My gages are pegging high and sometimes low. So, keep me posted on what happens for you and what was your fix.

-Thanks,
Brent

Oh yeah,
Yesterday, when it was acting up, the voltage at the cigarette lighter was 13.4 V.

Battery with car not running and car sitting for 5 hours: 12.6 V
Battery with car running: 14.3 V
Voltage at cigarette lighter with car running: 13.6-13.7 V

This is the first time when all BUT the oil pressure was working correctly when I drove it. Normally, my wife drives this car unless it is a ...

Thank you, I will check that out.
If anyone can think of more let me know because I am going to have the dash open and I would like to get it all checked out all at once.
Thanks everyone.

Here is the issue:
The displays are going in and out (mostly out) and the oil, temp, and boost gage will peg-high, peg-low, and bounce around inbetween. The car is running great but, the gages are disturbing and obviously can't tell me of any issues if any were to come up!
PLEASE HELP

Having worked on a lot of equipment involving gaskets, go with the Felpro just in case you ever have to do it again.

Please, only use the flare wrences if possible. Every other type of wrench will only round the nut off. Last time I did the fuel filter it had quick-release for both sides of the filter, but mine is a 1993.