Gangsta Boogie
+1y
to properly build a frame you should use a frame jig or frame table. the frame has to be kept straight throughout the construction process. A frame jig offers a set datum for measurements and reference and also prevents the frame from moving under the stresses created from welding. Also rememeber if you are stock flooring the new frame rails should be shaped to fit the "stock floor" so its not quite as simple as just running 2 pieces of tubing under the cab, you will need them to be in specific locations and you will also have to make or adapt a transmission crossmember.