I don't want to give anyone false hope, but as I pointed out earlier I saw two pretty big dudes three trains apart get moved from the front row to the back row. The first time the entire front row switched with the back row. The other time it was just the larger rider who got out and and switched with a single rider in the third row. I haven't seen anyone else discuss it, but there appears to be a modified seat in the third row unless what I saw was a twisted game of Chinese fire drill. And, I'd be no good at "guess your weight" carnival games, but the two guys probably weighed a little more than 260.
The back row is suggested for taller guests due to the tiered seating for the teeter totter effect. There's a bit more leg room in the back to make it less uncomfortable for most. To my knowledge, they do not have any seats that have a different style lapbar for larger dimensions.