Here comes information on my wiring.
Tachometer (Rev Counter)
Originally the signal to the tachometer came from the (-) on the coil but since I'm now using 4 COPS I need a different tachmeter input. A possible solluion is to wire signal from each coil with separation diodes into the cars original wiring to feed the tachometer, shiftlight and fuel pump relay.
A similar sollution is described at the bottom of this page http://www.megasquirt.info/ms2/EDIS.htm