Gotta love HD's instructions... for Rushmore era bikes, with fairings,
the Road Glide Ultra (FLTRU) is the only one that requires the extra harness to get power to be up and under the speedo (people have figured out other ways to get a power source too).
Beginning of instructions say:
Electrical Connection Kits by Year and Model:
- 2014 - 2016 Road King require separate purchase of 69200722
- 2017 and Later Road King and FLTRU require separate purchase of 69201599A
- 2016 and 2017 Softail and Dyna require separate purchase of 72673-11
- 2018 and Later Softail require separate purchase of 69201750
However, a 2016 Road Glide Ultra does also
Require the extra harness as well even though it doesn't say it there. If memory serves me it was the #69200722 that I had too get for mine...
But later in the instruction, under one of the "Installation" sections it's header says (seemingly including the early Rushmore FLTRU):
2014 and Later Road King and FLTRU, 2016 and Later Softail and Dyna FXDLS
Then at this point it gives instructions as to how to install the extra power harness...
But, simply put, as many others have said, All the Rushmore (& M8's) fairing bikes have both the power & interconnect (from the TGS) connectors under the gauges...
except the Road Glide Ultra (FLTRU). I Do Not Know For Sure About The Road Glide Limited's though, I haven't worked on one yet, but it looks like they come factory with heated grips... so its already got power up at the front too. The exception to this is going to be bikes that have been "modified" and people changed things around (hacking into power sources for other mods, changing bars and reducing wiring clutter, etc).
The Black and White wire's connector come from the TGS, and if you're having problems finding it under the speedo, trace the harnesses coming from the right switch pack and TGS and you'll find the little two wire harness splitting off the TGS harness. Mine was tucked in and hidden behind stuff under the speedo, just had to dig and move stuff around to find it. These black & white wires is where the "interconnect" wire (also black and white) from the new heated left grip plugs in, to get the power over to the right grip (don't forget to plug in the little plug under the right grip's end cap to complete the circuit).
Then the Red and Black wire's connector from the new left heated grip is for the grip's power source. Plugs into the Black and Purple (I think the Purple wire is actually violet and has a black stripe, V/BE) wire's connector thats already on the bike, and also under the speedo... it will/may have a dust cap on it that has to be removed. This is the "switched power" lead for the grips.