thanks for your reply, i'm still amazed with the quality of the bass(i'll post some pictures)...i don't know why the original owner replaced the pickup, i believe it wasn't a US pickup.
i was thinking about a SD antiquity but i've read pretty good review about bartolini pickup and they sound quite good on the JV, so i'll wait a little...
The electronic still works but i'm trying to approach the original precision bass sound, so i need some advices from the experts!
the current config is :500k pots and i wasn't able to read on the cap...
edit: i was thinking about orange drop caps and CTS pots.