im considering building my own sfc's either out of box steel or steel tubing. does anyone have and measurements and directions for doing this. im not totally sure on exacly where to mount them and what grade of steel to get. welders and cutters are readily available so just need the blueprints, can anyone help me out?? thanks

 

a36 will work fine, all you need to is get from one end to the other. jack your car up and take a look, pull a few measurements. look at some catalogs for pics or do a search here and you'll find picks. scrool down this page and you'll find a thread or two.