Lets try this again hopefully with better pictures and my solution to the issue.
The front two panels are too wide apart to properly support the smooth 1x6 and 1x8 center covers.
I glued in (so they wouldn't pop out) 2 1x2 with center axle hole pieces at the edges of the two front panels and tied them together with a zip tie. So far seems to be holding.
Other pictures of progress so far.
I also reinforced a few of the forward panel connections with 1x2 blocks with center axle holes, axles and 2 x 8 flat plates the same as done for the rear of the panels.