If you are installing a new blower motor, please
do not forget to change the regulator (transistor) at the same time! You don’t want to go back in there twice.
For the regulator, For my tastes I stay with MB or OEM. In my owners thread, I noted that I lucked out and found that the ACM I bought was a repackaged OE MB/Bosch regulator with the star scratched off.
For the blower assembly, also only buy MB or OEM Behr or “aftermarket” Behr/Hella Service.
BTW if I can change the blower motor, ANYONE can.