MCI MC5C Question - Automatic Transmissions

[Benjamin]

Is it true that the MCI MC5C only listed the Allison MT644 as the automatic transmission (for both the 6V71 and 8V71 Detroit Diesel engines), with the HT740 being a special order option not listed in dealer brochures?

I know the MT644 certainly was the only automatic that could fit behind the 8V71 in the MC5C without extra clearance, since the 8V71 is a longer engine due to it having two more cylinders compared to the 6V71.

The HT740 automatic transmission was both superior to and longer than the MT644, the "longer" part of the aspect being the reason I see all these posts (on Bus Talk and related websites) about the 8V71/HT740 not being compatible in the MC5C due to the overall length of the powertrain, but I did see posts about the 6V71/HT740 being a good fit for the MC5C. That bit being said, even the 6V92TA/HT740 combo, as used in the MC9 since 1981, could make a good-enough fit in the MC5C.

Could anyone please shed some light as to whether or not both the MT644 and HT740 were cataloged in the official MC5C brochures?

Thank you,

Ben (ClassicBusFan81)