Is the goal here to remove seating for passenger #5 and make for easier ingress/egress for passengers #6 & #7? I think the issue is that the LC is not a great people hauler once you get past pax #5. The "middle" row does not conveniently move for third row entry/exit and the rear seats are OK for kids, but there are so many better options out there as others have pointed out. The LC is designed for 5 and the third row was a marketing ploy - thanks, America. In other markets if you are serious about hauling people you get the 70 troop carrier if you must have an LC.Anyone successfully changed out 60/40 bench for captains chairs? What chairs work?
I know the 570 and the 460 both have captains chair options for the middle row...
Having said that, I bet there are a lot of third row seats sitting in peoples garages that they'd be happy to part with. I think fabbing a bracket to use another set of third row seats in the second row position might be the ticket. The existing second row seats are too big to easily get around even if you chopped out the middle 20%. You could probably weld in the same brackets that are used for the third row seats for use in the middle row and maintain some level of fold away access. I'm pretty sure I've been in an LC70 in Tanzania that had a fold down seats like that in the middle so you could free up the floor for standing through the roof and setting up photo gear.