I'm entered in the PI sprint this Sunday.
I don't think this gearbox is right so I've swapped in box out of white.
If you look back at white's old videos you'll see that the RPM drop in 5th is around 1400 RPM which is correct for a 0.91 5th gear.
This means that I'm also back on the wavetrac so I'll have a more direct comparison of the two diffs in the same car.
I'm pretty decided on a proper clutch style diff for the 02A when I get around to it.