Hopefully your trans isn't slipping 5-700 rpm at the shift points. Type F fluid has been a popular choice to firm up shifts and performance synthetic trans fluids tend to last longer because they are more resistant to heat and breakdown. I also preferred 4.2 kickdown levers.
If your shift lite comes on at 6500 and your data logger show 7000-7200, it means the engine revs 5-700 rpm by the time you physically react and the transmission actually shifts. There will always be some human and mechanical delay but the actual shift rpm should be determined by the rpm that the engine performs best at, unless you want to shift a bit lower to be easier on the engine or run a bit slower but keep a little ET in reserve and shift a bit later if needed. Like if you slip or spin off the line. Set your shift lite accordingly.
Theres a lot to be learned from data loggers and playback taches. They show what actually happens rather than what you think happens.
We're "human!" I loved my Autometer playback tachs.
Of course, in addition to a trans cooler, a higher capacity trans pan with the corresponding extension couldn't hurt either. There would be more fluid to absorb and dissipate the heat.
