The important thing when using a JP1.2 interface with a JP1.3 remote is to not have pin #5 connected.
If you cut wire #5 as close as possible to the IDC you should be OK.
This pic shows where you should make the cut. Make sure the cut has to as close as possible to the IDC header, if it is further away, it may act like a antenna, and you may not be able to use your cable.
