No big differences between a C6 and a 727. Both used the Simpson planetary design as did the GM Turbo Hydramatics. It was common in the 70's for Ford racers to put a 727 gearset in their C6 case. NHRA put a stop to this by checking for park in the transmissions because the parking lever wouldn't work in a C6 with the 727 gears.
I've seen Fords and GM scatter transmissions like a 727 in the past.
