The job replacing the heater motor had two benefits. After removing the heater motor, I was able to see the nearly completely blocked heater core. Bill R. told me to get hold of BG products Frigi-Clean solvent/conditioner for the core. First, I brushed all the filth that could be brushed out of the core. The product has expanding foam. I applied it to the front of the core, then with compressed air, blew it into the core, waited 10-15 minutes for it to soak-in. Next, I hit it with the most air pressure I had to blow it thru the core. Then I repeated the process again to try and get thru the entire thickness of the core. Along with the foamy cleaner, they include an anti-fungal spray to apply to the fan intake while the fan is running. I did that and it smells pretty good. Buttoned it up and WOW! The air volume I now have is probably double of what it was! I mean, it really sends the air flow out of the vents like . The car is a 11/90 mfg 535ia and does not have a micro filter in the design if you were wondering. Thanks again for the help and hope this post encourages somebody needing some of hte same attention. I intended to get in there after the evaporator next with the same treatment. Have a great weekend.
Now I am going after the electrical problem that plagues me.

Keith in AZ.