I got this for my main guitar and wired it into the volume position, it works great and is fun af and there is no extra holes required.
There are only 3 things you should be aware of:
1. The little lock the pot has when at max isn't incredibly strong
and can start to move downwards to the off position, how ever
this would be much worse wit out it.
2. When wiring make sure to put a jumper between the output
and ground nodes on the potentiometer and the holes on the
extension or else it won't work, spent to long trying to figure
that out. You can find diagrams.
3. The shaft is a little small in diameter at least for my prs se
custom 24, it was really confusing as I thought it would fit right
in but evidently not. To fix this I got some electrical tap and
wrapped it around the shaft at the length I set on it and use a
washer with the teeth and that seems to be work rather well
without any slipping to my surprise as I am not gentle with it.
Would defiantly recommend for your kill switch.