After much Google searching, I figured out the grinding I was experiencing sometimes, was due to having not glued the actuator housing back together. I originally simply snapped it back together and re-installed. Rather than glue it and not have access next time, I used some zip ties. Others have done this from the links I read and saw, and upon reassembly, it all fit with no issues regarding the zip ties. The first two pics show the assembly with the zip ties. This placement will not interfere with any reassembly or functionality.
Since I had taken the whole thing apart again, I figured I would really inspect the old motor and compare it to the new.
***Warning***; those of you that are not in to minutia and fine details need not to continue reading the write up. It may bore you to death, and I do not want to responsible for that.
Continuing on for those that dared. The new motor which was the Mabuchi replacement recommended on many threads is not quite the exact replacement. It is much louder and stronger on the torque than the original.
The third picture shows the end cap with the brushes of the original motor.
The original motor had a part number stamped on it "BN635624." The brushes were quite deformed, and worn out.
The fourth picture is of the new end cap from the Mabuchi replacement motor.
The armature from the original motor is slightly shorter in length than the replacement. About 3.7 mm's off. However this excess is in the end cap, not the magnet portion or commutator portion of the motor.
Based on this inspection, I cleaned up the original armature, and used the original magnet housing, and placed the new end cap from a second motor I had purchased as a spare. So essentially what I have re-installed in the car is the original motor housing w/magnets, original armature, and new end cap with new brushes.
The fifth picture shows the two armatures side by side.
After re-installation, the motor is as quiet as the original, and it functions as is should. Also by reusing the original armature, I was able to have a correct D shaft, and not a grinded one from a dremel tool.
I share this for future do it your-selfers. The write up in the beginning of this thread by the OP is quite good, and was relied upon for completing the project. So a big thanks the OP for getting me going.