Hi chaps
Ages ago now I installed the GK kit into my bass, to drive the V-bass unit.
You can choose to have LEDs, switches, buttons, control knobs etc when you do the install, and omit them as you wish depending on your tastes. The only things you NEED are the output and the pickup itself.
I chose to add the control knob to my bass (which is assignable depending on what I'm doing (for example it's a wave shape control on a synth, or a pickup balance on a jazz bass model).
I now fancy adding the 'up' and 'down' buttons to select patches without using the pedalboard. Problem is, I can't find the ones that came with the kit. I have emailed Roland to see if I can get some spares, but failing that, I wonder if anyone knows if they are a common type I can replace with something sourced elsewhere?
Here's a picture of the kit contents, the buttons are the matching two black items
Here's the .pdf showing how the thing is wired up (mine passes through a Marleaux 3 band active pre-amp, too)
http://media.rolandus.com/manuals/GK-KIT-BG_OM.pdf
It should be fairly easy to add the buttons to the circuit I think.
Cheers
ped