I would take a picture of what is in there now but I'd be too ashamed. It's something I've cooked up myself ( in a hurry to get it running ). Now I'm not so sure it's reading right all the time with cable flex, grit etc. The best way is to mount the TPS on the end of the throttle shaft, no flex there!
The ball valve should make a good throttle valve,when the ball valve is open there is no restriction to airflow, no gaps, no needles, no butterfly, nothing but a nice big bell mouth straight in. Plus it shortens the intake path a little more too.
Jeram, what happened too this Bighorn road racer guy that was going to get back to us? On NATF