I got an email from Paul today that my Promaster conversion is 60% done and will be ready in two weeks. I didn't even know they had started!
I'm sad that I didn't get a chance to take pictures at earlier stages of construction, but I'll rush over to Austin tomorrow and document as much as I can. And knowing that I'll get it two and a half months before I expected makes up for a lot. Now I have only two weeks to shop for insurance...
I doubt you still want an answer at this late date, but there are seatbelts for 7 -- 4 across the back, one on the side bench, and driver and passenger seat. We've had seven people in it surprisingly often, and they claim that 4 people across is decently comfortable. At 18.5" each, it's more space than people have sitting 3 across in our old Honda minivan.