I read a webpage about a guy who said he adjusted his high idle screw to get his truck to rev to 3000 rpm. Is this a good idea and if so how do you do it?

 

i have done it on a few trucks, mine will hit 4800 real quick with the high idle screw laying in the door pocket of my truck. but i know of other pumps that don't like the screw removed.

 

I wouldn't recommend it, the governor will stop you from gaining more than a few hundred rpms that have very little torque. The way to gain rpm with power is with a governor spring kit. If turning the screw was worth much people wouldn't be buying GSKs.
The 1st gen engines can benifit from turning up the high idle, could have been what you were reading about.

 

It was a 95 2nd gen and with a #10 fuel plate said his top speed went up from 97 to 114. You can write whatever you want about a truck on a website though. Mine has 1000 hp, see I just did it.