I don't know if this will help anybody but it might. After I removed my A/C I ended up with only the three lower fan speeds on my defroster blower motor. I have been studying the shop manual electrical section and finally figured it out. Removing the A/C wiring also removed the ground for the high speed relay which disabled the high speed function. Running a new ground which is the black wire going to the relay reactivated the high speed relay. Now the blower motor is operating as it should.