I just sent off an order to Audere for the classic 4-band with 4 knobs - volume, balance, high-mid/treble (split), and low-mid/bass (split). Gold satin knobs if it matters
. I also ordered some conductive-adhesive copper shielding tape from another supplier.
Here's a pic of the 765A pre-amp cavity with the cover off - the cover has aluminum foil shielding - the cavity itself looks like it has something gray sprayed inside but the coverage isn't good.
I'll start another thread and post some pix of the conversion when it's done. Keep chatting meanwhile and thanks for the replies.