Here is SurferNicks write-up on it. The hardest part would be having your stock Honda stem pressed out of the lower tree and having it machined. I lucked out by finding a set of wide glide trees that SurferNick made for bigarmzz. Thats the stem I am using. The stem I have wasnt made how he describes in his write-up and it still works just fine.
1. Have stock stem pressed out.
2. Have the very bottom 1/8" of the stem machined to 1-1/4".
3. Measuring 3/4" up from that needs to be machined to 1-1/8".
I had to remachine mine to get the 1-1/8". It was slightly larger.