Jazz bass mismatched PUP options

[mindflow]

I tried to search for an answer to this, couldn't really come up with anything...

Part 1
I have an MIJ Fender Jazz 75 RI I bought years ago on eBay and it has a Basslines pickup in the bridge and a different pickup, I'm assuming stock in the neck. The bass has a constant hum even if the two PUPs are at two same volume level.
I'm assuming this is because of the different PUPs but could it be the bass is not shielded?

Part 2
Also I am trying to figure out what I should replace them with if I decide to go that route, I would like to find something close to the 70s sound, growly and good for rock, any recommendations? I just looked at the Aguilar 70s models and they sound like they might be on the money but a little steep for 160

[impactwrench]

you probably need to find out if the basslines pickup is single coil or humbucking. if its single coil, I think you need to resolder 2 wires to make it out of phase with the neck pickup and it should probably be hum cancelling then.

[mindflow]

How can I tell if it is humbucking? And should I save my adventures in learning how to solder for the pros and just pay someone to do it? Sounds like something cool to learn but I don't want to mess anything up.

[impactwrench]

well, if you can figure out what model it is, you can check the website. I am not at all familiar with SD pickups. You probably need to take the pup out and look on the bottom for a sticker or see if it has 2 coils side by side (EA and DG strings). Or if its a stacked humbucker I dunno if you can tell by looking at the bottom.

[mindflow]

Thanks for the help, I'll check it out. I might end up switching them both out anyways for a more vintage sound, just have to figure out which ones I like