The previous answers really said a lot of the critical stuff. One of the things I did was cut out my trees and the support dealy thing out of wood. I also cut my rockers out of wood and it enable me to mock the whole thing up with the Honda neck. I was able to adjust my leg length and change around my rocker design till I had what worked with my springs. This also allowed me to check my trail and make sure it was dead on. Here's some links to my shutterfly account with the process I used. I hope it helps.

This is them in wood
http://motorheadsbuild.shutterfly.com/28

This is after I got them cut out in metal
http://motorheadsbuild.shutterfly.com/68