George,
I'll give you what limited info I have from many discussions this year with some converter guys.
I am sure some experts can shed more light, but this is my understanding.....
Pump vane angle has a larger effect on the top end. You may be able to tighten up the top end, usually to a max vane angle of 40* - 45*.
The stator design generally has more effect on the bottom end. If you were to cut the stator you may get better spoolup, and may only affect the topend slightly.
So I guess it is possible to do both at once depending on how your converter is currently setup.
I know there are more things that affect stall speed than just these two things, but I believe these are the two that have the most effect.
If I'm off track, I'd like to hear more about it from one of the tranny guru's on the board.