Heres a picture of my 13 row. Its an 8 row front frame with the outer 2 units taken off the front bar to make it a 6 row and has 7 units in the rear. I pulled it home with a 1/2 ton pickup but this planter is nearly balanced percfectly in transport position with negative tongue weight so it kind of whipped the pickup if you went too fast. You can sit on the tongue and push it down.

As far as the chains, it only drives from the lift wheels on one side. The rear part is driven by a long chain from the front. It works for me. Only compliant I have with the planter is the flimsy markers. And also I wish the front bar had 8 units instead of 6. I may overhaul it someday and make it like that.