Greetings,
I've now modeled the 5 seats, and reworked the interior, now the headlights "light" up in the renderings! Hooray!
[see my blog for more pictures]
If the top of the sides at the rear need to be strengthened, I can add a sliding rod at the top corner of each door at the hinge side that adds a 3rd anchor point (the 2 hinges plus the rod) that forms a box corner? The two rear doors will also latch together and form an end gusset and if the hatch door has 5 or 7 anchor points (2 hinges plus 3 or 5 latches!) it will all lock together pretty well, I think. If this is the only issue I have, I'll be ecstatic!