How do you bypass or adjust the clutch safety switch on a 1989 F150 4x4?

The clutch switch is located in cab between the brake pedal and throttle. It is mounted on the clutch rod at the firewall. You should replace it, not bypass it.

I agree, replace it, don't bypass it. It's there for a reason. Normally I have nothing good to say about Chilton or Haynes manuals, but the Haynes manual gives a really good description of how to adjust the switch.

cross the red and the yellow wire leading to the neutral safety switch to bypass it