I would agree the /6 bell housing is unique – but they did install A727’s in police and taxi F and M-bodies. It could even be special ordered for FMJ’s. The first gear ratio on A999’s would make the /6 A999 much more desirable than an A727 – but that’s not the point here.
I have worked on and overhauled quite a few /6 A727’s for cars and trucks – all with 1-piece aluminum cases. That said, the car /6 A727’s were all in police or taxi’s (for some reason, the police are hard on their equipment, taxi’s, not so much).
The A904 (A998/A999/A500, etc.) pan gaskets are almost the same as the A727 pan gaskets are – all except for one corner – the Right Front corner.
This is to help elaborate on
@Camtron post a tad.
A727
A904 (or variations).
Both pictures are looking from underneath the transmission and the bottom edge of both pictures facing forward.
Bud
Edit: I did a Google search for a /6 727 and couldn't find one - but I know for certain they exist. The pickup/van version is a whole lot more popular than the car version is, though.