I just did my sub-frame connectors this winter using a different approach that what i have seen done. i took a length of 1" x 2" x .100 wall tubing and spanned the length of the sub-frames starting at the point where it goes up for the wheel well at either end. Welded it under existing sub-frames allowed me to have 12"-14" of overlap to weld to . some work to clean the undersides of the sub-frames and a little notching to get it to fit properly. but overall very satisfied with the results. allows room for emerg brake lines and other misc. provides a conduit to run stuff from front to back. (left the ends open, just cut a 45 degree angle at both ends for aesthetics) sorry i don't have pics! the argument will always be that it would be stronger if ties to the floor but I am running a 45 year old floor that probably could contribute as much to the structure as the bond to the entire underside of the sub-frames. LIGHT ,CHEAP, AND EASY!