click on this link it is in the technical section of this forum. You will find the service manuals and wiring diagrams available to download onto your computer:
crossfire-problems-repairs.html

seems like you are doing the right things to correct the problems. The warning lights will go out after short drive when the problems are corrected. The A/C may start working after you get the fan problem corrected, so don't mess with the A/C until the fan is working correctly. Sounds like you need to do a complete flush and anti freeze drain and replacement. Use only the correct anti freeze ( Zerex G05) when you replace the thermostat.
There is a good group of Crossfire owners in Maryland. Check the clubs section near the bottom of the forums main page.
Good luck and have fun with it; When it begins to seem too much like a job, take a break.