Brian:
I actually moved the attachment points from the front and back (where there were pre-drilled holes) to the sides (and drilled my own holes) because the outside corners were a lot beefier. Thanks for the advice, I will watch it. I let my daughter put it through the "jungle gym" stress test and it all seemed to stay put.

I was actually contemplating putting reinforcing bars of slotted UniStrut around the uprights. I figured it could beef it up some and the slots would give me lots of lash poits for keeping gear on the deck. I'll see how it goes.

Regards,

Marcel