IMO, that's not the best way to approach it.

If ET's are more of a priority that street manners, then put the appropriate gear and converter in the car now.

If you're trying to keep it as street friendly as possible, then understand less stall and gear will yield slower ET's....... And that's the compromise you're making.

The dual purpose car is much much harder to get to live up to the "on paper" potential of the combo than something that can be optimized without concern for street worthiness.

I still feel a trip to the chassis dyno would be worthwhile place to start.
This does a couple of things......
-let's you see what the fuel curve of the carb looks like
-gives you an idea of what the upper limit of the usable power band is, which helps with converter and gear selection
-gives you some hp/tq numbers you can if into some calculators to see what the car "could" run