Milano automatic exhaust differences

Does anybody know what exactly is the difference between a 5-spd and an automatic center section on the Milano? There is very little reference to the automatic version on the sites of most parts suppliers, although many mandate their center sections as 5spd specifically. IAP seems to have made note of a part number for the automatic version but has no price or page for it. I'm wondering if the demand is just so low that people don't stock/sell them.

Luckily it seems that the rest of the system is identical.