hi every body

i am half way through refitting my interior in my mk2 and i have got to the rear floor and i am stumped.
my interior is stripped out and has a rollcage. i have ditched the rear seats and want to flush the rear flooring so that i can carpet it and make it look nice and clean.
i was thinking of building a frame to sit on the floor and level it out so that i could lay MDF or thin marine ply on top and then carpet this to finsih it off.
has any body else done this to a stripped out motor. how did you cover the rear strut towers and rear light cluster wiring ?
does any body have any pictures of interiors that might help?
cheers