Drilled bycicle handle caps iand installed PTT switch. Tried various methods to thread the wiring through the sticks. What finally worked was threading a #22 gauge wire from the bottom, heat shrinking the PTT wires to the threaded wire, and then slowly feeding the wires though.
Connected the PTT ground wires to the seat ribs, together with other grounds. Routed the PTT wires to the avionics shelf.