It took a while but I verified the fuse to the blower motor relay was good and also the fuse to the blower motor. I swapped the relays and still no help. I took out the passenger front seat to give me access to the blower motor and then removed the blower motor. A bench test of the motor verified it was working well. I did blow out a lot of fine dust.
I removed the speed resistance selector device from the engine side of the firewall and found it extremely dirty at the connection. The wire (spring) coils were clean. Lots of fine dust came out as the ¼ inch spayed terminals were pulled loose.
Electrically all was still in place meaning no burnt spots and continuity everywhere. So I wire brushed the lugs until bright again and cleaned with alcohol. Then reinstalled everything and all works fine as designed. Bottom line I think there was enough dust and corrosion on the terminals to cause and open circuit.