Good morning, Bill
That will be a very interesting project to follow. I have used that three man vs adjustable cranking previously on a Pickup upper door jamb, but it was less than 40" long. I would make sure that the three of you practice first and do it right before lunch. Right after lunch the coordination seems to be lacking somewhat.
Is that chassis the one that I would have seen when we attended Ben's Mechammer seminar at your place last year? If so, it was very nicely done and in great detail. Your shop is well equipped and you will enjoy the progress. Take lots of pictures and keep the pictures flowing. Maybe you could even find some local 'yocal' to take the occasional video for you.