i want to revalv my fork

You have it a little reversed, there. Low speed damping effects bottoming resistance more, and high speed damping effects small, chattery, sharp hits more.

Check your sag numbers to see where you are currently at with spring rates. Then you can go from there.

First and foremost, get a small log-book and start taking many pages of notes as you tweak your clickers, oil height/weight, and sag settings. Honestly, most stock suspension just needs to be adjusted a little and can make worlds of difference without a revalve.

BUT... honestly, the YZ KYB forks are a complete headache in that model year range. Chances are, you will need the compression stack changed a little. My YZ is about as good as it will ever get without subtanks, and still doesnt hold a candle to the newer Showa or newest KYB twin chamber designs.

Get your sag right where you want it, get your oil changed front and rear, and see what you can do with the fork oil height. After that, let us know your base valve shim stack and what the bike is doing that you dont like.

Suspension Tuning

I am looking to do the same thing and have found the most useful advice and information from Race Tech. Just google them. Paul Thede is the founder of Race Tech and has been doing this for many years. His insight is priceless and his products are top notch. Also on this website they have a fork/shock spring rate calculator that determines what the optimal size of shock you need. They also offer tips on oil viscocity, oil height, and different types of valving. Hope this helps! Keep the rubber side down!