Hi...
Just a small update. I extended the holder for the IR receiver.
My sound board has an IR transmission for the trailer and it's contructed as a contact thru the kingpin.
The original holder is a bit to small, the IR receiver can only be placed with a piece of double sided tape.
So I took a small piece of tape, removed a bit on one side and soldered it on the holder. Now I have a holder for the cable also and I can fix it correctly.