Mod questions

Good day all!  I'm wanting to do couple of mods.  The first interior adding a shelf to the back over the window where the permanent bed is.  I would like to use some L brackets and attach a shelf that hopefully can use the pre existing holes that are used with the window valences.  Must admit I'm nervous about messing with the walls being a brand new camper.  Thoughts on brackets screws and mounting would be much appreciated.

The second idea is we are thinking about getting a spare tire bike mount for the back of the Pod.  Our bikes are light and can't imagine the mount to be real heavy either.  Thoughts on the weight back there and being safe while towing?  Thanks Mark

Molly bolts huh, I'll look into that.  Aside from looking out for the normal wiring areas what kind of thickness are with this walls?  I want to be sure on the bolt size, thanks again!

Woah cool some different things I hadn't seen before as far as Ideas go.  My biggest concern is actually just drilling into the wall.  Guess I'll start small and see how far after the initial hole before the final wall to go with the molly bolt.  Thanks again all, super useful!

As a counter point, we use the 3M hooks and have never had one come off the wall, even when holding multiple wet "sheet" sized towels.