lose the washer bottle, replace it with a kangaroo bag

but do you think it will get enough air flow in that corner

yep plenty, it doesnt need to be waving out in the wind. If you want more air run some ducting from the front to the air filter.

My air filter is in the corner. i cut a 100mm square peice of metal between the light and the radiator support, i had the same thought u had when i was getting putting mine together, seems to work fine, but as tyrie said if u need more just runn some ducting to the filter.

you can see mine here, i found that the intercooler pipe was always hot so i shielded the pod with some bent ally, this also ducted air from the hole in the radiator support

i have never put the shield into the ute though, its hard to tell with these things, unless you had some thermometers from jaycar or whatever i dont think you are really going to notice the difference