Heater motor won't shut off

Not sure I can help. You admit you have adapted and changed the wiring. Best I can tell you is you effed up somewhere in this. I would download whatever service manuals deal with whatever year(s) you mixed together. Go through the diagrams carefully In some years, the diagram for the A/C electrical is not in section 8, it's rather in the AC/ heater sections of the manual

Many many years are available free at MyMopar.com. Some of them there are the efforts of guys right here