I like velcro as well. The hardware store has strips of velcro maybe 6" long by 1/2" wide, with one side fuzzy and one side hooks. They may call them "wire wraps", or some other name, but they'll be with all the velcro. Glue in a piece of balsa or two, with a slot cut for the velcro, and use the velcro strips to hold the receiver and battery in place. The nice thing is it has a little give, that protects the receiver in a crash. It's also possible to just glue down the velcro strip by soaking a little 5 min epoxy through it onto the bottom of the fuse.