There is a 2 pin connector where your ecu is located (passenger's side right kick pannel). The connector is blue/green and looks like it would plug into a 2 wire male end connector.

You take a paper clip, make a U shape with it and stick each end into each connector pin so that you jump it.

This makes it so your ECU won't try to compensate for the timing adjustment. Then set your timing. When you're done, remove the paper clip.

HIH