I like the look of two strips each side, but didn't have them on the Plus 4.
I would avoid pop rivets, just because I find them difficult to drill out without drifting off-centre, and the aluminium formers are thin.
I think the best option for a refit is double sided tape, with plastic pegs to locate properly. A length of plastic rod could be used - heating the top of each short length to create 'rivets'.
