Cant get the rear bench in

The front bottom connections goes in first. You have to lift the back of the bench up and slide the u-shaped connections under the rods. Once there in, then lower the back of the bench. The back has latches that should spring open and around the rods in the floor opening. You should be able to actually drop the back of the bench and they should "seat", however it is better to place the back of the bench on top of the rods, and using the lever located on the bottom of the bench - open the latches; causing the latches to grab the rod.
Let me know if this helped, or if you have any additional information, problems, or questions. Feel free to contact me at FixYa.com!