1990 Montero engine rotates -not firing

My 1990 Montero's engine rotates but will not fire from the ignition. We changed the distributor, ignition coil, power module/ transitor and wires going from the distributor to the sparkplugs.  But it still will not fire. The computer is good. The timing belt is ok, but no pluse or spark from the coil.

Any idea where is the ignitor/ signal generator is located? Is it inside the computer? The manual shows it as a small box with 2 connectors. 

Any suggestions would be greatly appreciated.

check your alternator??.......check over all the wiring components

Are you sure its a spark problem and not a fuel problem?  When you turn the key to the on position can you hear the fuel pump?  If so do you have any pressure in the lines?