Difference in RWHP between manual and automatic?

[Bandit]

I know a manual transmission frees up power over an automatic transmission--but how much, percentage wise? For example, going from a TH350 auto with a 2500 stall converter to a manual TKO-600 5-speed, as I did with my car. I know the best way to tell would be run it on a chassis dyno with both setups, but since I never had the chance to dyno the car before the swap, I can't do that.

Also, is rearend gear ratio a big factor in rear wheel hp? Say, if you swapped from 3:08's to 4:11's.

I am sure there are other variables, like autos with lockup converters that would change the results, but I am just looking for a general estimation.

(I am sure this has been discussed here before, but I couldn't find it with a search.)