I've heard that there is an STV running around Simi Valley, California, that has had an automatic transmission installed. I haven't seen it myself, but I've heard about it.
There isn't any reason that I know of that you could not use an SVT engine with an automatic, but I'm not sure how well it would run. The SVT likes high revs, higher than the automatic will let it run without modification. I think the SVT cams would work better with a stick, and that the non SVT cams would work better with an automatic unless you made modifications that permitted near red line shifts at full throttle, and perhaps a little lower final drive ratio.
