I have been trying to chase down a hesitation at about 3000-3200 only when cruising. It accelerates smoothly and runs strong. I have one of Dave's new TPS boards but have not yet put it in. The hesitation is there if the TPS is plugged in or unplugged.
I have noticed the dwell changes and I wonder if I have a bad distributor. When I wiggle the distributor shaft, there is some slop. How much is too much? Should the distributor shaft wiggle at all?

The shaft should spin freely and NOT wobble. Wobble is bad. If the dwell is dancing around, no good.

Sounds like you need a new/good one.

"914itis" on this board has one available. P.M. him about it.

I have a similar hesitation but at lower RPM's and coming off idle. Let us know if/how you get it fixed.
Good luck,
Bob