Hey! I am looking for a way to modify the passenger seat of my Rad Runner Plus. I use the bike mostly to transport my 6 year old daughter to and from school. She is still in the Thule seat (she is on the petite side) but is outgrowing it. I've seen people adding the backrest and handle bar set from Amazon to the back but I was looking for something more secure, like the Caboose offered for the Wagon. Has anyone found something like that for the Rad Runner? In my search, I've seen the Yoba Monkey Bars and the Tern Clubhouse MadPad but was curious if anyone has retrofitted these products to fit on the Rad Runner. I also saw a couple of items on Amazon that had a backrest with a bar on each side, but nothing that wraps all the away around. Has anyone tried these?