This says the harness is the same for 2 to 3 speed:

https://board.moparts.org/ubbthreads/ubbt...ch-harness.html

Different switch connector plug of course. You can remove the terminals from the connector and then wire it up.

Linkage info:

http://www.passion4mopars.com/Mopar-2-Speed-to-3-Speed-Mopar-Wiper-Motor-Conversion_b_1.html