2001 merc Sable

Are you talking about doing something to the part itself or removing the part from the car?

This is a seal unit and no serviceable parts available from the manufacture
and should be replace as a unit

Although the manufacturer has decided to market the part as a complete assembly with the HVAC housing, the heater core alone is readily available in the aftermarket and routinely replaced in the old housing although it is a quite extensive dis-assembly to access it.

I have been advised that your part number matches a blower motor and not a heater core as I had assumed. That makes BMRFIXIT correct. More detail in your question would have been helpful.