Do it yourself. You wont mess anything up.
You can buy the snapon kit, 4k GSK, and rack plug for a little more than $350.
Then you can set it however many times you want.
http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=16323&group_ID=2964&store=snapon-store&dir=catalog
The price bs&t mentioned also includes changing the valve springs. I know his typing is a little hard to follow LOL