For my car I thought about having steering wheel mounted shift buttons however they wouldn't fit in with the overall look of the car and I preferred the option of having paddles behind the steering wheel so off to eBay again I went.
I picked up these paddles for £15 that came from a Golf R32. They are solid aluminum and have a tactile feel to them. Pressing them simply operates an internal push switch.
I decided to dismantle them to see if I could modify them for my needs. Again, probing with the multi-meter I found a pair of contacts that are bridged when the button is pressed so I soldered a new cable to the contact and routed it along with the existing wires.
Mounting the Paddles
Next I made a cardboard template of the steering wheel spokes and boss mounting hole positions. I then headed over to LibreCAD to draw up a template for a new mount.
The cables will be routed along the back of the mount and into the steering wheel boss. I am hoping that I can use the spare terminals on the standard rotary coupler to interface between the steering wheel and car wiring loom. The advantage of this approach is no unsightly cables and no issues with getting tangled.