Forget the acceleration rates for the TC selection; that is a different matter entirely, and is a side discussion to what you want. Use what was summarized in post #12.
As for the best shift point, it depends more on how the torque drops off below the data presented in your dyno sheet. If the RPM's dropped from 5400 to 3200 RPM on a 1-2 shift for a 904, then what is the torque at 3200? Can't tell from the data... IMHO, for drag racing, you would upshift at the point where the after-shift torque is roughly equal to the pre-shift torque... i.e, you evenly 'straddle' the torque peak before and after the shift. (And I can see it varying from there but that's 'in the ballpark'.)
