From the BBA-North America email received this morning, OC Transpo 8011 was present at the Scottish Vintage Bus Museum Open Day. Here's the photos below:
(Source: DD03 BUS' Flickr http://www.flickr.com/photos/66812080@N03 )
Same position as before, right behind the driver. If you go to Alexander-Dennis's website and download the "go-anywhere" brochure, you will notice that the lower deck layout is similar to normal buses.
From the previous post's pictures, you can definitely see the gas tank (normally located at the top of the right front wheel) moved to the rear right of the bus.
B12 and NZ's Kiwi Body Enviro 500 are mainly for charter work, therefore they have a more continental style tourist double decker layout.