I'm sorry to bring this subject up, I can see that there are millions of threads about this already. I have now spent days looking, reading but not smarter at all.
Years ago I had a Maton JB4 fretless with
Bartolini 9J1 pickups and an EMG BTC replacing the tone controll. The bass sounded so sweet and i loved it so much until it was stolen.
I see all the EMG diagrams with easy plug in systems, extra red wire from pups connecting to busbar and so on. I would love to see a good old fashion wiring (soldering) diagram for passive pickups like my Bart's in my jazz bass connecting to the BTC, correct pot values and such. Simple diagram to replace tone control and what wire to solder where.