[quote name='KiOgon' timestamp='1424859333' post='2701162']
I would suggest a new wiring kit would go a long way to solving all your problems
[/quote]
If only there was somewhere BC'ers could get a handmade, solderless, high quality replacement bell plate with everything already attached that would just drop in to the existing cavity... eh Kiogon?
Seriously though, the 500k linear pots should ideally be 250k logarithmic for passive single coil pickups. 500ks will deliver more top end to the output jack, so this might account for the increased hiss that you're experiencing.
Whilst you've got it in bits I'd recommend shielding the cavities too (including pickup routes as well) as the single coils don't reject extraneous noise (mains interference, emf etc...) as well as humbucking pickups do. If you're desperate then glue and tinfoil would do it, but I picked up some self adhesive metal foil for doing flashing on roof tiles or something similar. Works a treat.