The absolute best wiring diagrams that exist are on line at
www.startekinfo.com it will cost you $25 for a day and you should be able to get more than you need in that time.
All forms of writen diagrams would have you lost. I spent about 15 minutes trying to find what powered the Z connector I mentioned and I basically knew where it came from and I thought I knew the diagrams. I had to search out the K40 relay and knowing that was where it was I found it. Online there would be a link at the node Z 7/39 taking one to the next drawing or to a number of orther possibilities like color pictures of locations, legend information, and rarely some technical theory.
The drawing online are also in color so following a wire is made easy.
I thoroughly recommend that everyone with a 98 or newer car view this site on a day you wish to invest in your car. There is an amazing amount of info there, basically everything I would have to work on cars. So much that you will never understand all thats there in one day.
If you go there for wiring diagrams be sure to read the specification list in the menu (left side). Basically telling one the type of computer etc. There are three files/programs that must be installed to do everything. You must have adobe for the WIS but you must load a file with a yellow icon (program escapes me) to view the wiring diagrams, I had to get tech help the first time as I'm not to computer literate (took a week and they did give me three days..... so maybe you should do it my way..)