Disclaimer : Sorry don't know who drew this ...
And this is my take on it :
If anyone one wants to accurately build it, let me know & will do some more sketches ...

As far as doing the 'mod' for this I think it would be relatively easy : Remove the back seats, boot & turn it into a tailgate ( Optional to make a hard cover version ). Cut the roof just behind the B pillar, then slide the rear window forward until it meets the back of B pillar + cut the side windows down to fit. Knock up some inner panels for the tray, then form up some ‘tube rails’ to go round the tray edges, turning up & over with a ‘roll bar’ somewhere near the B pillar, paint it red, and lastly put a few spotties on it.
Bob’s your Uncle …

Cheers, Bantum ...
Note : images should work now ...
