James,
I just did this on my 70 Charger 4 speed. Now I have the 3 speed wiper and I do not know if the wiring for the 2 speed wiper is different or not. My car was missing the 2 wire plug (shown in your lower picture) on the wiper harness where it attaches to the bulkhead connector. I contacted Kim at passions for mopars and she supplied me with the proper set up. The trans harness is self explanatory so I will skip that. With the 3 speed wiper the other half of the harness the black wire plugs in above the brown wire into cavity D and the black w/ white trace plugs in above the red wire into cavity C. Then plug the harness from the trans into this harness. Now I also have the dash mounted reverse indicator light and there is a third wire that plugs into cavity Z on the engine side and the indicator light plugs into the same cavity from the passenger compartment.
The switch on my trans was also bad so I ended up replacing the entire system as the trans harness was also damaged. I hope this helps you and I did not confuse everyone. If you have a factory service manual it is on page 8-98. If you don't have a FSM you really need one it is one of the best investments I have made to figure out all the little electrical gremlins.

John