What are you trying to achieve?
A second hand MEMS unit cannot be paired with an EWS, in fact all of the ECM types once paired with an EWS cannot be paired with another EWS.
If you are replacing a defective MEMS unit with a second hand one, the 93C66 EEProm can be removed from the original unit and fitted to the replacement, meaning the rolling code is the same as the one expected by both the EWS and MEMS.
Hope this helps
Brian