Mazda 787B question

Hi all. Busy with the Tamiya Mazda 787B, and I've removed the doors for more detail. Lots of CF in the interior, so it should be nice when done. Needs a lot of scratchbuilding though, as there are major gaps now between outer body and rear bulkhead etc. Also needs a firewall.

The reference pic shows what appears to be a roll cage (below fuse panel in corner)? Anyone have info/pics on this, also need better pics of interior (especially details re rear bulkhead, fire extinguisher, electronic control units, footwell)?

http://files.automotiveforums.com/gallery/watermark.php?file=/502/361518304-5_Small_-med.jpg

try my image collection zorpia.com/peteri click the album section you 'll find all photo of 787B