There is a rubber plug in the driver's side of the Tremec TKO transmission that plugs a whole which is meant for the mechanical speedometer pickup/sensor. The rubber plug is for shipping and should be removed for driving the car. If you are using the electrical one on the passenger side then this rubber plug should be replaced with a steel one. I bought a steel plug from Mike Forte. In the following photo the rubber plug is the black round thing with the vertical tab running across it. Note that the black bolt immediately to the right is something I had to buy to hold in the new steel plug and I just had it placed there for safe keeping. the bolt is a 1/4 x 20 x 0.75 long bolt. (I opted for the harder steel one which is better for auto uses.)
Below you can see the metal plug taking its place which has a tab on the right with a hole that lets the bolt tighten it down.
Something else I thought I would play with is seeing if I could move the passenger exhaust tube that connects to the header so that it would line up better with the body cutout. Here is is when I put the body on:
Here it is after a little fiddling.... An improvement I think.