#1
First off, hey there.

I bought a JA set, put the wiring together and it all worked lovely, sounded incredible . It doesn't actually fit inside the existing routing though. Before you try and tell me it should fit, it doesn't. It definitely does not. There is no way a 9V battery will fit under the solderless system. I stopped trying to force it because I was just going to end up hollowing out the screwholes holding the control plate down. For reference, my bass is a US Standard Jazz, going by the serial no. it's a 2010 model. I'm not sure if the routing is any different in other models.

So, I cut the clips of and soldered it back together following where the clips went. Should work, right? (right?) Well, it doesn't, which leaves me a bit confused. The neck volume seems to work, but the bridge and tone not so much.

Am I being an a spanner for not getting the solderless system to fit? Has anyone tried to solder these in? Any pictures or diagrams would be really helpful.
#2
Are you sure you didn't knock something loose trying to shove the battery in? There are some external 9v holders you can purchase too if you don't want to rig something on your own.

I'd check all of the solder joints / connections.
Guitars:
Ibanez RG1570 Prestige
Jackson Kelly KE3 - MIJ (Distortion/Jazz)
Jackson DKMGT Dinky (EMG 81/85)
ESP E-II Eclipse Custom (JB/'59)
ESP LTD EC-1001FR (EMG 81/60)
Fender MIM Strat

Amps:
Mesa/Boogie Dual Rectifier Roadster 212
Laney IronHeart IRT-Studio
Peavey Vypyr 30
Peavey ReValver Amp Sims
TOOOO many T.C. Electronic Pedals. . .
#3
Also, don't tighten the little nut on the pots too tight. I did that once, and I kept wondering why it didn't work anymore. Turned out the pot's frame was deformed to such a degree that it got rekt.