I can't help you on the regulator question. However, regarding the motor; I used ATF to lube the shaft ends. It's quieter and spins smoothly and faster now. The squirl cages are expensive, be careful with them. Above the motor is a 2 piece cabin filter. Release the lower driver's side catch, slide out bottom piece and then second piece will slide down and out. Rotate the [6?8] clips to remove top half of heater motor housing.

Unfortunately, you have to remove the wiper assembly to remove the heater motor. It's easy, but time consuming because all the plastic shielding below the windshield has to be removed before the wiper assembly. It's also a good time to open up the wiper assembly and motor's transmission to clean & lube.

Bob
PS I did this routine this month, so if you need more specifics, ask.