For reference, I described the electronics wiring of my Brian May Red Special replica in detail this article: https://dsgb.net/projects/redspecial/part60/
As I mentioned in the previous article, I re-purposed the electronics which I deployed on a previous iteration of my modified Fender Stratocaster. I connected the switches using jumper wires from a K&H kit available from Rapid online: https://www.rapidonline.com/k-h-ks-350-jumper-wire-kit-box-of-350-34-0495
This allows a solid mechanical connection which confers a reasonable degree of structural rigidity to the assembly. The switches were spaced more closely on that pickguard so some desoldering and modification was required before I could connect longer jumper wires between each bank of switches. I wired up the components in the same way as my 3/4 scale Brian May Red Special ensuring a good mechanical connection by wrapping the solid tinned single core around the connection lugs before soldering with a non-RoHS compliant high lead content solder. I used lengths of black, red and green 7/0.2 mm 26 SWG PTFE insulated equipment hookup wire for connections where some flexibility was required, including twisted pairs of ‘tails’ to temporarily connect the pickups.
With the preparation stage complete, I re-made the previous connections with longer jumper wires.
After installing the pickups, I marshalled the positive, negative and casing earth wires of the pickups to follow the cavity routing, bundled them neatly using small black cable ties then wired the final connections.
FInally, I added some small sections of heat shrink sleeving to the soldered joints, soldered the grounding connections into the control cavity, adding extra copper foil in the ‘tail’ section to ensure good electrical continuity (not shown in the picture below) and tested the assembly. If you scrutinise these pictures, you may notice that the red and black wires are reversed on the switch lugs on the bridge pickup on/off switch. This is because in the previous deployment on my Fender Stratocaster, the bridge pickup was specified with a reverse polarity magnet and thus required to be reverse wired.