The best way to install electronics is

Passive soapbar pickups, I presume... This diagram will work.

JazzBass_1V_1Bld_1T.pdf

The pickup type doesn't matter as long as they are passive (no battery needed) pickups.

 

Probably best to take it to a tech. They can determine what parts you need based on the pickups, and wire it all together.

Then again, assuming you don’t have active pickups, you’d probably be fine with jazz bass wiring, and I’d recommend 500k pots and a .047 to .1 uF cap... Or, make your life easier and get a similar solderless harness online...

 

Let's start with your bass. What is it? Next, what make & model are your soap bars?

 

Assuming the soapbars are passive (which you haven’t confirmed yet - how many wires do they have?), the diagram that @Crater posted above is exactly what you need. Study that diagram and post back here if any questions remain!

 

You need a book then, not a forum.

https://www.amazon.com/Guitar-Elect...coding=UTF8&psc=1&refRID=J6MHV18VK7SFY9P35585

Bass and guitar wiring is very "generic" - it doesn't really matter what brand bass or pickups you have as far as whether or not they're "compatible". The main issue is whether or not your PICKUPS are active or passive. Most "active" basses in fact have passive pickups with an active preamp.

Active pickups are almost always made by EMG and will have three wires, colored red, black, and white. A passive soapbar could have two, three, four or even five wires. This is where you really must have a multimeter to figure out which wire is which, especially with a 4 or 5 wire pickup. EMG makes passive pickups too, so not all EMG pickups are active.

The Seymour Duncan diagram I linked to earlier in the thread shows the specifications for "compatible components": 250 k Ohm pots for master volume and tone, a 0.05 microfarad capacitor for your tone control, and a 250 k Ohm blend pot. Again, this is assuming you have passive pickups, which they most likely are.

You will have to make sure the components you buy are mechanically compatible - that the shaft is long enough to fit through the body, and that the top of the shaft is the right type (splined of solid) for the type of knobs you want to use. Splined pot shafts used splined knobs that push on. Solid shaft pots use knobs that are held in place with a set screw.

You can buy these items on-line at Stewart-MacDonald (StewMac) guitar supply or MojoTone. There's other sellers too, just search for guitar electronics.

Regarding the con-joined bodies: did you think this through? I can't help but noticing you're perilously close to the threaded inserts that hold the guitar tailpiece down. If your router bit hits that threaded insert when you're enlarging the control cavity, you'd better be wearing safety glasses.

 

had the same thinking when i saw the weird picture...

i'm sorry for the OP, but, what a weird project... it makes me feel uncomfy