How do you fix the dash light on a 1997 Nissan hardbody xe extended cab?

The question you ask is too involved for a proper answer. You need to go to a car parts store, and get a repair manual for your car. They cost about $16.00 Or, go to a Public Library.

I also know from experience that the car parts manuals (Hanes) has nothing on these problems what so ever.

It depends on which light that you are looking to switch off im not familiar with that model but I know that the Micra has a number of lights, there are answers on this website for the air bag light, and it doesn't involve buying new parts. These codes appear to work for all Nissan models so worst comes to worst give it a try chances are it will solve your problem without an outlay.