Hi there, SD people!

I recently picked up a Yamaha Pacifica 812V: really nice guitar to play, but I'm not entirely satisfied with the sounds.
It has a TB-4 in the bridge and SSL-1's in the neck/middle. The humbucker and the single coils are unbalanced tone-wise: the SC are too bright compared to the HB and vice-versa.

I have seen a couple of videos featuring Suhr and Anderson guitars that had similar pickup configurations (output-wise), and they use a special wiring so that the SC "see" a 250K volume and the HB "sees" a 500K one. I would like to have the same thing going in my guitar.
I am pretty new to guitars, and don't know a lot about electronics. I have seen some diagrams and learned I would have to wire a 470K resistance somewhere to do that, but I haven't found a diagram which was like my guitar. The closest I've found is this: Name:  hss.jpg
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I guess R2 and R3 are there for the SC to see a 250K volume, but what are R1 and C1, C2, C3 for? It looks like the tone knob has no cap. Is it correct?

My electronics are as follows: 1x 500K volume, 1x 300K tone. Super-switch, same amount of terminals as the one shown in the diagram. The tone knob is a push switch to split the bridge pup (outer coil is active). Auto-split in pos. 2. I don't know what cap I have for the tone knob (I know it is orange, which seems to be a good sign ) Stock knobs, so I guess they're linear taper.

I would appreciate your help so I can understand these diagrams and do this nice little mod in my guitar