I have a few questions for you Rickenrockers! (see what I did there

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I've always loved the Rick sound, specifically the high gain bridge pickup, but I already have 4 basses and can't see myself buying another one in the near future. That being said, I love tinkering and customizing what I do have, and I want to make them all as unique as possible.
My idea is to switch out the bridge positioned jazz pickup in one of my 4 strings to a high gain Rick pup. A little different maybe, sure, but I'm imagining the tonal possibilities when mixed and matched with the P-bass pickup in the neck!
I've been searching around the Rick website and can't seem to find any detailed info on their pickups. No dimensions, tech specs or anything like that.
So here are my questions (all referring to the high gain pickups):
1. What's the difference between the high gain neck and bridge pickups from a technical stand point? Are they wired to sound different? Or is the difference in sound due only to their positioning?
2. Does the whole mounting system for the bridge pickup have anything to do with the sound?
I ask these two questions first, because a neck pickup in the Rick boutique is 75$ whereas the bridge pickup is 150$. If I can get away with getting the neck pickup and getting the same results in the bridge position as a bridge pickup would, then all the better.
3. What are the dimensions of pickups themselves (both bridge and neck)? What string spacing do they allow for? What are the total dimensions including mounting holes/hardware?
4. Are the high gain pups active or passive? And what value of pot should I match them with?
Anything else besides this I should know about?
Thanks guys!