Distributor
I chose to use the stock Toyota distributor as a trigger.
Note, These wire colors are for the 1991 engine. the wiring harness changed in 1993 and yours may vary. I know for a fact that the All-Trac harness is different.

First, download or print the Haltech/Stock PIN OUT Diagram located in the 'Downloads' section.
Go here to get a PDF document identifying the Distributor PINS, and how to wire the stock distributor to the correct E6K wires. Distributor.PDF

Locate the wires in the stock harness and splice the Haltech harness to the stock plug and the Haltech harness.

WIRING NOTE To wire the E6K to the stock Distributor
Pin A is a Red wire, this goes to the Haltech Blue/Red wires
Pin B is a White wire, this goes to the Haltech Green wire
Pin C is not used. Cut the wire lead to the ECU*
Pin D is a black wire and goes to the Haltech Yellow wire
*NOTE, If you do not cut this wire, the trigger WILL NOT WORK. You must cut the wire from Pin C on the stock distributor connection or your engine will not run.

If you choose to splice in the E6K wires to the distributor, and want to locate them at the ECU
You can download a PIN OUT Diagram of the ECU here ECU PIN OUT Diagram
For the Distributor, the Red wire is PIN G-
For the Distributor, the White wire is PIN G2
For the Distributor, the Black wire is PIN NE