Your comments about wanting to get into the tens make me think a bigger cam, single plane intake, bigger carb, and restalling the converter to 5,000+ is the way to go. And it sounds like you don't have a cold air system? That is leaving a lot on the table.
I would do any gear change last. Consistancy at this power and speed level come from back to back 60 ft numbers, and accurate shift rpm. When i was running 9.50s and went to an airshifter with rpm switch, i saw my times narrow by .02. Having the 1/2 shift happen further down track is a help, and once you have the cam/converter combo up well above the torque peak, the old rear gear ratio has less
Effect on ET, but good effect on cosistancy.