1995 Chevy 454 intermitant hard to start

The relay I found was the heater blower. So continuing search under dog house I found another relay but it turned out to be the A/C relay. I checked out under the steering column, didn't find anything. Went back to the oil pressure switch and unplugged and cleaned. (forgot it was unplugged) Went try to start, Got chattering but no start, Now it gets weird, Plugged oil switch back in, From that point on key switch is dead. Now the only way to start is to use the MOM switch ! When running everything works normally. Turn the key switch off engine dies and nothing works again no head lights dash lights turn signals or Kwicki step. Hit MOM switch (don't have to hold ) everything live except key switch have to hold MOM then key switch works. I am up a tree, Checked every fuse I could find and all good. With engine started Chassis Battery 13.3 V Coach Battery charging at 14.4 V. Chassis Battery is brand new Les Schwab 84 mo. does not appear to be getting charge from alternator.
Regarding oil pressure switch, The engines starts shows oil pressure at gauge. No leaks around it. Hopefully someone here has some ideas where or what to check. Other wise I'm off to a mechanic tomorrow.