AAHHhh the pickups preamp switch-a-roo thing. Dude this is a street you will have to go down to cure your mental disease if your are like me. There are some really great sites out there with exact dimensions and helpful info. Bestbassgear.com rules BTW I have bought tons of stuff there. And always have a great experience.
Dude no matter what anyone says you will do want you want to anyway just like I did but please remember a couple of things after you realize 90% of the time it’s a mistake. Pickups and preamps are like rims on a car. You put $1000 rims on a Hyundai it still sucks but now it looks even dumber. Pickups only reproduce the tones of the bass they really don’t improve them so as awesome as any electronics or pickups could get if the bass is a lower end model it’s really won’t sound better actually it could get worse.
I have read threads on Talkbass years ago about this very same thing and most of the time everyone reported even after upgrading everything on an instrument that was underwhelming to begin with over and over they almost every single time sold it anyway and just lost their ass in the process. Even after being warned I upgraded 3 Euro Spectors at the cost of hundreds of dollars and sold them anyway. The one and only time for me it has been successful is this last time with a complete overhaul of my Warwick Streamer but now I have some hum crap I can’t figure out but that’s another story. Well good luck you’re going to do it anyway but just remember “I told ya so”. I’m not trying to be a prick man I swear I’m just trying to save you some time money and aggravation. It is cool to learn about it and try it out. Lefty wiring is enough to make you want jam a wire brush up your ass but it’s something us guys do I guess. The pickup thing not the brush. Sell the $400 basses and buy a good bass that sounds great off the wall…different rims on an Audi A8 will all look bad ass and will perform great. The same rims on a Prius will only make it suck more.
Please know this is just my experience and you may find completly different results after all I had a couple nice Fenders and sold them in weeks because I thought they were some of the worst made and sounding basses I ever owned. I know I could get stoned for that comment because other guys here have them and they sound increadible and I wish my tone was as good so don't listen to me.
But in my experience, I've found that the ONE thing that can drastically change an instrument's tone for the better is replacing the PUP(s). Granted, it won't make up for a lousy build, bad pots, hardware, etc., but it's usually a good first start. The Fralin I just recently dropped in my '73 P was like night and day compared to the original PUP. Not even close.
