I'm not sure if you want to try this...
I was talking with some of my regular technicians today (I'm squeezing as much insignificant warranty work in while I can). I asked them about a problem like this. I was told that it could be the shift cables warming up because of the exhaust location. They have heard/seen the shift cables being warmed up by the heat dissipation from the exhaust on the Contours and Mystiques. I'm not sure if the routing remained the same on an SVT Contour.
One of them suggested you could drive down here to Waterloo and show them. They're an SVT dealer as well.
