Looks like no one had any suggestions on this one...thats OK though because at long last I figured it out.
I replaced the pressure switch to no avail - as as soon as I turned the pump back on the pressure would immediately climb nonstop over 100psi. I guessed correctly that the switch itself wasn't getting pressure from the nipple. When I removed the nipple it was almost completely sealed with mineral deposits. I replaced the nipple and everything works great.