Warwick Corvette RB $$ Replace Input Jack

Hi guys, I'm a real bassist's bassist and I have a practice later today and an instrument with a broken jack that needs replacing, only I don't know enough about this to be wholly confident in what I'm doing and thought I would ask before wasting time, money, and solder on doing the jack wrong. Any help is greatly appreciated!

So the bass is a Warwick Corvette RB $$ and in the electronics compartment there are 3 wires, 2 black wires and 1 white. I was doing some research last night and it seems that one of the black wires is supposed to be purple? IDK, very new to this stuff. Anyways, picture attached, the input jack itself has 3 terminals for wires, a short one, middle one, and a long one. Can anyone tell me which number goes to which terminal? You'd be saving the band!