Great review.
Adding a tone knob is an easy mod, since that thing has the same huge control cavity that my Stars does.
This should give you a good idea of a comfortable place to locate the extra knob. With my guitar, the original was in a very
Friedman-esque spot. So, I made it the tone, and added a push/pull for the new volume knob. The JB-7 sounds great tapped.
If you ever decided that you can't live with the EMG, but still love the guitar, you can get the pickup ring I used from
Frets on the Net. Just drop Dave a line and ask for the 7-string EMG to passive conversion ring I used.