Vans moulded stick grips PTT installation

[chris mitchell]

So I settled down to wire and install my. Ewly arrived grips. I need the cookie hat and a PTT. The website says the grip can be drilled for a second switch - the moulding has a suitable hole for the coolie hat.
Has anyone installed the PTT and if so - how? Where should I drill? The obvious spot is just in front of the coolie hat?? Then how do I secure the switch and run the wires?

Feeling clueless!

Thanks

Chris