A couple of pieces of wood shim should be plenty of protection for the hoses. It won't take very much pressure at all. You're just trying to stop air from leaking in, not meld the sides of the hose together.

I don't really see the significance of how much fuel is in the tank. Or the need to drain it.

To avoid all of this, I installed a small inline hand pump in the fuel system to prime it and push all the air out. It works really well. You can find one at your local marine supply store. I can put on a DRY fuel filter and start it on the first turn of the key.