So, now that I am an expert, Alvin, can you see why its not best practice to put the residual valve on the frame rail? All of the fluid from the frame rail to the drums (or discs) is kept in place, but the fluid before the residual valve to the MC is subject to backflow. So to me this would not be a good thing at all because it could result in the squishy pedal you are trying to eliminate. Without Bart and the way he likes to humiliate his victims, where would we all be? Nonetheless, I get it now, so thanks? If I decide to install residuals, once I figure out which ones to get, I will put them as close to the MC as possible. To find an incline high enough to park my truck at the angle for this to matter, I would have to drive about 300 miles living in central Kansas and all.