I hope you have a lot of tools, free time, and know how. I'm not saying that you don't but I know first hand that that shit aint easy, and I've been welding and metal working for while now. As far as the measurements go I don't know of a sight. But the way I would go about it is to find a pic of a bike that I like the rake and stretch order a frame like that and measure for your front legs(forks I mean).