Not sure about the mounting process but I think you might find that the length of the extra cab tray would not be legal on a dual cab ute. I forget the exact dimensions but there is a restriction on tray size / overhang.
Your mounts wouldn't line up. I have a single cab size tray on an extra cab (how i brought it) and it is more of a hinderance than a help. Two things straight up are that i can't get a hi-lift under the towbar and it won't fit in my shed. So bigger is not always better in this case.
Cruiserdog wrote:Looong!! Nah it's not to bad. My only real gripe is not being able to get hi-lift in. I'll try and post a picture up.
Interested in those pics, I'm thinking of something similar to fit on a "Tradies Canopy" for a camping fitout. Whether I use a tray mount or a chassis mount will depend on what I can find by shopping around the wreckers web search.