Mick. Can't believe the typo errors I'm making trying to keep up. I'm still thinking about what you said at the start of page 2. So working backwards>>>
I think a man of your talents could come up with something pretty cool along these lines. If you are going to have a fixed roof, what about this> build a bar type rack if you need to but run a couple of extra long heavy duty slides underneath with a fixed alloy panel covered in PVL solar panels. Run a sail track around the outside for a mozzie screen or canvas curtain, etc. That way you don't have to mess with a tarp and it will get the solar out from under the load (or small boat) when you are pulled up to a campsite. (Remember that the PVL's are 2800mm long)
Those bars look pretty tough. Ever driven a 550? Shame fuel is the price it is cause they are so sweet. I love 'em. Here is a couple of bars we did ourselves. Wierd how the 550 4x4 is the only Isuzu model (I think) with the lights on the bar hey? These were made to clear the cab when tilting it.