The flat face of the seal goes away from pressure, so the flat faces go against each other, inner seal flat face towards outside, outer seal flat face toward inside of motor...
Just did a quick check of the signal paths on 2015 wiring diagram, magneto pickups front and rear go direct to ABS unit, pulses varying in frequency representing speed leave ABS module on pin 8 / Blue/White wire then feeds LSU (mis labeled in diagram) ECU and combo instrument. 2018 is similar...
On the 15 /16 MY bikes the ABS tone rings supply a signal to the ABS module that is at a much higher frequency then what is sent to the combo instrument, the ABS module divides it down and supplies a cleaner lower frequency pulse train for the speedo. The wheel circumference can be adjusted in...
Here are a few with just a quick search of the web, there are some threads here on the forum also...
https://ktmtwins.com/products/lowering-kit-1
https://aomc.mx/KTM-LOWERING-KIT-390-DUKE-20-21.html
North American bikes do not have the wiring for euro mirrors with indicators (2015), it is not hard to add the connections as the same signals travel to the instrument cluster and you can just splice into that part of the wiring harness. I thought had a post with pics showing mine and how...
This info is based on earlier model 2015 / 2016, not sure if it is same on newer models, LCU is called out as A53 on page 8 of 9 on diagram and is located on left side of bike on frame near battery box.
At this point I don't think that it is binary, I have found pics of the sensor with wiring and plug and it appears that 2 wires are for crank pulse coil and 3 for gear sensor. I can likely figure something out but not with out a newer sensor and a complete wiring diagram.