Yes , that was my favorite pickup for a while. No idea why I moved away from it tbh. Less shrill top end and it sounded chewier . FWIW I used 500k pots
My experience with just lowering a pickup It tends to sound weak and lifeless versus having it up a little bit higher to the strings, but it’s possible it could work OP just needs to try it. To answer the OPs question about the Duncan custom shop , I used to order from them years ago and they...
I would put a rough cast A5 magnet in the your JB first and see if that does the trick . It will mellow out the pickup just a bit but it retains all the qualities of the JB . Simple and cost friendly mod