Revenator / coil

You shot yourself in the foot. The FItech works fine with a coil NEG trigger which that box had. Juz sayin......
My electrical engineer friend with a oscilloscope and I were able to determine this box is providing a 9V tach signal which FItech says wont work, you might be right but I have already replaced this set up with a MSD unit so my loss could be your gain