I'm not pushing this but trying to be helpful. Buy this setup http://www.s197forum.com/forum/showthread.php?t=79418 that I have for sale and you will have the best of both worlds. You can shift like it's a manual, without all the clutch problems and have the advantage of an auto for the track. With this setup you would need the trans crossmember and a drive shaft. It would be much cheaper than going to a manual 6 speed.
Earl
Earl