Thanks for all suggestions on Blower Motor on 1991 300 E. It is fixed. The protocol I listed workede quite well in Identifying the Blower Motor regulator as the "Bad Actor" 1.) 12 Volt Battery supply voltage spun the motor.
2.) Getting 12 Volt reading from motor supply wires ( apparent low amperage as 1 amp fused short would not even blow the fuse from this 12 volt supply.

3. Running a supply wire from the terminals from behind the fuse block Master Cylinder spins motor

4. This step bypassed the blower regulator.

5. Found one (over phone )for $10.00 in salvage yard but since he had to remove blower motor to get to it I had to take the blower as well for a total of $ 75.00. (It looked better than the one I had.

I was corrected by someone that Regulator was "not" a series of resistors and I did know that. I was simplifying its function in the circuitry. I suspected a lot of resistance activity in the the tiny pitch pot as it is attached to a huge (relative to its size) aluminum Heat sink (Porcupine)

More good news! Junk dealer had a broken (parts unit) Windshield wiper transmission that I got a replacement circular rack gear and restored the oscillating feature to my wipers.

Finishes up another project working on these wonderfully designed cars that can still frustrate you when the designs are unique or we don't fully understand (or appreciate them) until we have them figured out.

Thanks a Bunch,
Don