If the bracket you posted works for you, then I would say you already found what you need.
I don’t really have good work in progress photos… I just walked around Home Depot and bought various metal angle and L brackets and drilled them out to make it work under the hood to hold various items securely.
My air compressor isn’t under the hood for longevity / heat concerns. I have a portable on an Anderson quick disconnect in my grill.
I'm actually inflating my air mattress here... but you get the idea.