So the Hipshot Kickass bridge squier specific is the way to go.
Next question:
What Jazz bridge has anyone actually installed and is it enough to keep up with the existing P neck pickup and sound good with it? I've heard of people talking about installing one, but I hadn't read anyone that has and if the one they installed was a good match for the existing P pickup. Or heard clips.
Or:
What PJ5 pickups have you installed? What were the results?
Anyone try the neck nut inserts?
Thanks! (in advance)
I've put various Nordstrand, Duncan and Dimarzio pickups into 4 and 5-string Jazz basses for people, and for better or worse, there was always a noticeable change in the way the instrument sounded. My favourite passive 4-string Jazz setup is a pair of Dimarzio Area J's.
I've done the same thing to 4-string Fender and Squier P's. Noticeable difference in every case. For a vintage vibe, I personally prefer the Fender AVRI pickup. It has more bark, but a lot of people like the Nordy, which sounds just a little rounder and smoother. The QP definitely has it's own thing, higher output and rather exaggerated.
Regardless of which one you prefer, there's always a sense of having gotten some value for your money.
A couple of us have put the 2008 and up Am Standard Precision V pickup into our VMP5's, and to be frank, the difference isn't overwhelming. Audiences are not going to notice the difference.
There's a YouTube before and after video featuring the Nordstrand vintage 5-string pickup. You'd have to listen to it yourself, but personally I would call nice, but not it a $134 Improvement. TBH, you'd get a bigger bang for your buck out of a Tonestyler or an active preamp.