When I built my Kitfox, I attached all the many panels for my fully finished interior with Velcro attached with "Shoe Goo". In a few cases, where I wanted to make sure there was no slippage, I put a wrap of light safety wire around the tube over the velcro. After 7 years and 700 hrs, nothing has come loose ( I had some epoxied wire supports that did.). Velcro is cheap, easy and very lightweight.
Velcro can stick extremely well, if you are concerning with it coming loose, Bob Nuckolls has an article somewhere on his site where you clean the metal with Acetone, warm the Velcro glue tab and stick it all together into something that's near impossible to remove. Couldn't find it offhand, but its a good site to browse anyway.
