One of the issues was strange noises coming from someplace in the back when going around corners. I had already dug all the way down and removed the spare looking for the issue. Maybe there was something in the gas tank? The second time I took out the spare I looked behind the battery area and found a golf ball. Before long I had pulled 6 golf balls out of that area.
The kit arrived in less than a week in a relatively small box. It was only about one foot square in size. But everything was there.
The HHR did not come with a back seat. It had the metal frame that was designed for use with storage bins. The storage bins list for $700 from Chevy! So I made my own storage area using some plywood.
I will need to make some wood trim to go around the outside edge. Here is the view from the back side.