I looked at this also - I thought you could get 25mm+ by moving the rear screen flush with the 'back of the B pillar' then what you do with the section where the tray meets the rear wall is all just metal/panel work. ( cant remember how much room before you get to the tank)
I'd thought I'd do some strengthening in this area seeing you'd essentially be cutting into a 'unibody'.
I'm only 5'7" and had the standard 'thin' seats re-upholsered to keep as much room as possible.
Still a few more inches would be nice ( off legroom of course :))
Got sidetracked onto other projects and put it on the backburner but Good luck if you decide to go ahead and show us the results.
D

You can move it way back for more interior storage



Or way, way back for a rear seat



Tassie style

thanks for the reply

It's been done a few times over, some quite well and some pretty bad.

There have also been 'space-cab' and 'double-cab' versions which are pretty bizarre.

Someone has once cut the wall just under the rear window and flipped the section of wall and re-installed it so it provided a bit more room.

has anybody tried to move the rear cab wall back to make more room in the cab?