Congrats on getting it passed. I had a similiar problem passing the emissions test in Virginia with my 1992. I'm curious what your plugs looked like when you replaced them. How did they look?

I ended up replacing both O2 sensors because I was running way rich especially on the right bank. The right O2 sensor was really hard to crack loose and I had to pull the starter to get to the plug. That and a can of "Guarenteed to Pass" had the numbers below 2007 standards and the tech scratching his head big time.

On the heat issue, I would definitely check out the wiring diagram mech259 posted and at least bypass the relay to make sure the lower fan works. The fact that the temp drops when you start moving makes me think air flow is the issue. If the radiator or thermostat was the issue the temp would most likely rise at speed.