GV makes a version for the PG (now) that splits gears, making the 2-speed a 3-speed with the overdrive, but also creating an intermediate gear between 1st and 2nd.
This can be done manually with a 727 conversion + GV, not sure if it's possible to do electronically (rather than try to juggle both controls).
The results for a 727:
1st 2.45:1
1st + GV 1.91:1
2nd 1.45:1
2nd + GV 1.13:1
3rd 1.00:1
3rd + GV .78:1

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