I installed an MTG Mid-scoop/Tone switch from Rothstein Guitars.
My aim was so add a more realistic "acoustic" tone to this already versatile guitar.
To my (perhaps naive) surprise, I discovered there were no holes underneath the pickups - just tiny ones for a single wire. Everything has to be done through the bottom f-hole.
Since the MTG's inductor is attached to the "wide face" of the pot's switch box, there was no way it would go through.
I therefore detached the inductor, de-soldered the two links, attached it "end on" to the bottom of the switch box, soldered in two new links, and secured it with string. I could have used epoxy, but decided on a "softer" adhesive plus a loop of string.
It's not pretty, as I'm not very experienced in these matters. But it went in quite smoothly, and I am very happy with the result.
The volume knob on the Kingpin II has a bass bleed cuircuit, and this is able to change the tone in a good way. When playing the bridge pickup, turning the guitar volume way down, and the amp volume way up, it gives a nasal honkiness to the sound - great for (what I describe as) a retro British sound. Likewise, playing both pickups through the "acoustic" emulation channel, having the guitar volume down gives a more acoustic twang to the sound.