and emergency flashers not working. Also the cabin air control switch will not redirect the A/C, everything is going thru the defrost vents. I have looked at/checked fuses and such. What else should I suspect?

 

The heater control problem seems like a vacuum problem. Check the small plastic vacuum lines that run along the firewall under the hood. Also, the 96's had a problem with engine oil migrating through the vacuum system from the vacuum pump and sometimes ending up in the heater control head. If it gets into a vacuum actuator on the heater box, it will swell and distort the rubber diaphragm.
I think the turn signal problem is a separate issue. Maybe a multifunction switch.

 

did you check the flasher unit, square black or aluminum box on your fuse panel, and it has a separate hazard flasher but I had to upgrade to heavy duty flasher, about $10, because my trailer has so many lights.
Good luck