pickup arrangement for fretless project

[paul torch]

Hi, I have started my first project bass. I'm converting a Vox "Standard Bass" to a fretless. At the moment it has a fender P style humbucker set-up which is positioned right up against the bridge. I was thinking about placing another set of pickups closer to the neck to give me a deeper sound. Can anyone recommend a pickup type, j-bass or p-bass?
I understand that most basses have the J pickup near the bridge and the P pickup near the neck, is it essential to have them in this configuration or can they be swapped?

[BassLife77]

I would put a MM style humbucker near the neck. pop in a preamp and a series/parallel switch. the bass will rattle the walls

[paul torch]

thanks, I'll look into it