Tech III and throttle bodies will not be cheap, but you already know that
. Ive got a set of 40mm Webers I can loan if you want to try them out. They need rebuilding, but I was planning on sending them to JW's shop in the near future anyway.
Have you called someone like Andial to see if they can tweak or customize CIS for a little better perfrmance? It may be a minimal gain, but it might be better bang for the buck than TEC3 or even carbs. Ive heard there used to be a guy (from Louisiana actually, and regretfully out the business now) who used to modify CIS to be more perfromance oreiented for one of the big Porsche shops out west.