Its the throttle body that's modified. The original old school method is to follow the instructions in the direct connection bulletin. It makes a very positive shift. The fact that there is no automatic shifting after the modificication is a side effect. Good for racing with column shift too with 'cause you're slapping the selector away from Neutral. With a pushbutton, just don't miss the correct button! T/A, A&A etc now have a variety of flavors for manual shift kits.