oil pressure guage

For a while now my oil pressure guage-stock- has been acting weird.
It would mainly show no pressure and when I came to a stop/parked...it would sometime peg at max... or sit right where normal line is, basically it jumped all around.
Yesterday I changed my oil and installed a new oil pressure sending unit while the oil was drained... when I added new oil and got wiring hooked up my stock guage was pegged and hasn't moved since.
Today I got my triple A pillar pod installed with boost, A/F, and new oil pressure guage... I did as the instructions said... Wire from sending unit to correct post on guage, Ground wire to solid ground, and the only thing I did different is instead of the "hot" wire to ignition I hooked it up to another power source that is only on when ignition is on. My new guage is pegged also. I unhook the signal wire from the sending unit and it still pegs when I turn on the ignition.
WHAT HAPPENED!?!?!?!?!?!?!?!? I double checked and everything is correct by the directions...

Any Suggestions?

when you hooked up the oil pressure sending wire from the unit to the gauge, did you make sure it was away from any moving parts? it may have snapped like mine did...i fished it through the steering boot and it got wrapped around and snapped when iw as driving one day... also, did you have to extend any wires? not sure if it really makes any difference, but in the instructions it says if you have to extend any wires, be sure to use only 18g i think? pretty sure it was 18. i don't think that would be the problem though. also, did you install the sending unit that came with the new aftermarket gauge?

It said nothing about wire guage...
wire is still in tact and yes I put on the new sending unit that came with guage

hmm that's odd.....possibly could've blown the new gauge? sounds like everything is hooked up properly...1 wire from sending unit to correct spot on gauge, 1 wire from ground (i put my ground on one of the nuts on the inside of my door, it's visible when you open the door), 1 wire from a power source (i connected mine to the ignition switch and ever since then my ignition switch has been acting up, but still works) then you have the power and ground for the backlight. hmmm...maybe you could TRY hooking it up to the ignition switch but i don't think it should make a difference...if worse comes to worse, take the gauge back and get a new one. where'd you buy it at? maybe they could possibly tell you if it's blown.