I kept all the seat heater wiring, switches and relays in the flap actuator area and shortened the wiring as much as possible. The seat heat high/low switches are on the forward part of the flap actuator brace and easy to get to. I totally agree with the poor quality of the wiring, so ALL the wiring forward of that is Tefzel, a DPST power switch on the panel with the heaters on separate parts of the switch, and each with their own fuse.
That way I have an easy way to cut power to the system if things get busy, Summer time, or any other issues.