I am planning to build a P-51 Mustang 1:1 Replica. I will make it flyable. I have all the parts/pieces from the structure ready to cut and assemble. From what material and what thickness should I use for this structure to be strong (to support human weight) and also light in the same time ? Steel, aluminium ? And what thickness ? 1, 2 or 3 mm etc. ??? Thanks again.