I found that article in my magazine scans collection... Good thing I must not have read it back in the day. ;-)
My system worked perfectly for years until I got a 2000 and sold off the Toolbox. But then, I'd already installed a DKB Kwikstart board to eliminate the need for the kickstart disk. That also included a new PAL and the 'grounding mod'. I even ran a heavier ground line out to the toolbox's ground plane. I also never tried putting anything on the passthtru of the toolbox... I was sure that would never work.