Hi there
Entirely without prejudice
, I would suggest you purchase 'The Halftrack in Canadian Service' published by Service Publications. It contains a number of photos of M14's in use.
It's available here:
http://www.servicepub.com/
In a nutshell, though, photos show most M14's were not fitted with a rear door and I would assume the partition was not a solid panel, but had an access hole. With the top up there was not other way into the rear but through the front doors.
However, here is a shot from the book, showing what looks like an M14 (see the side folding armour plates) but with a rear door!
Never say never!
Steve
