Hi Graham, PBG store states:

Pit Bull Guitars MMB-4 Electric Bass Guitar Kit Includes:

Basswood body
Maple Neck (bolt-on) and Blackwood (engineered rosewood) Fretboard
34″ Scale with 24 frets
Chrome plated hardware
Humbucker pick up
2 volume and 1 tone knobs
Chrome machine heads
Lead
Strap buttons
All electronics (pots, caps, wires, etc)
Set of Bass Strings
FREE Shipping – Anywhere in Australia
Level of Soldering Difficulty: Novice
This kit contains everything you need to build a complete, playable guitar, except your choice of finish.

Wiring diagram found here.... https://www.pitbullguitars.com/wp-co...MMB-4_2014.pdf
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The control plate comes pre wired and if connected like above it should work? I butchered mine and added a pre amp so not much help in that regard. The diagram is suggesting that volume controls are working independently off each of the humbucker coils and also has a master tone. Therefore, when all on '10' it should sound quite full and meaty but as you back off one volume the level would drop as well as the depth of tone, then switching the other way does the same on the other coil. The difference in sounds is very subtle between front & rear coil and when combined with drop in output level you may end up just leaving both volumes wound flat out.

Cheers, Waz