Custom Guitar Wiring Kits | BCS Custom Guitars Custom Wiring Kits. If you can’t find the wiring kit you need for your guitar we do make custom kits as well at reasonable prices, we will just need some information from you first and we will send you a quote. What we need are some photographs of your guitar so we can be sure to build your kit to fit. Control Plates and Wiring Harnesses – Sigler Music 920D Custom Shop handwired harnesses, wiring kits and control plates feature all top shelf components. They are designed to easily drop into your guitar to transform your tone.