The probelm with the back "bumper" is that is for all intents and purposes soley a poop hose container. Useless for all intents and purposes other than that and carrying your spare. Way too thin to consider adding some steel tubing to make a usefull area for extra storage.
My opinion of course...but have been in the welding industry for a
fair amount of time...
Anyway...this is what I did - light and strong.
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I realize that not all will be able to do this on their own..but not too hard if you have a welding machine and know how to use it...in either Alum or light wall steel HSS tubing.
Rgds,
Stk