This might help your question on gear selection; I'd advise get a few hundred RPM's inside your cams power-band at cruise and lockup, so as not to lug and get good fuel efficiency.
Pretty cool website. I totally agree with how to choose a gear!!. I have a non lockup converter so it makes things a little easier. I deliberately used a non lockup because a lock up converter sucks trans fluid pressure away from 4th gear. In fact, the only time the converter does lock up is when the tranny is in 4th gear, I believe it's designed that way. Since 4th gear is the weakest gear it tends to fails first. Losing any fluid pressure to the converter (so that it lock up) only decreases the life of the tranny because once 4th gear starts to fail (for lack of pressure) it puts trash in the system and then it's just a matter of time before the whole tranny is ruined. Everybody probably knows all this anyway!!