I've never used the Thompson finisher but check out this page here on FAOL:

http://flyanglersonline.com/flytying...ners/part6.php

If you watch the video the demo is based on a right-hand tyer and yes, its turned in a clockwise direction. Now, if you were to turn everything around (fly points to the left) you'd now have the orientation of a left hand tyer. And the whip finisher would be in your left hand.

At this point can't you wrap the finisher in a counter-clockwise direction i.e the same direction that you've been wrapping your thread all along?