Like the 7D (and 1D4) I want to be able to switch the control dials. In terms of ergonomics, it makes much more sense to be able to control the shutter from the rear dial and aperture from the top dial as it is much more accessible. This is the way that I've shot for years and the 5D2 is missing the custom function.
For the 7D, this is shown near the bottom of page 220 in the manual: http://gdlp01.c-wss.com/gds/0/0300002580/01/eos7d-im-en.pdf
If this is out of the realm of this project, that's fine but thought I would check. Thanks