Boot Floor Stupid Idea

This may be a really Stupid idea but to go with my plans for galvanised inner front wings, in debating how much of the boot floor and rear arches can be replaced with alloy or galv pannels.

I'm thinking of getting new iner and outer rear arches pre fitting them and then having them galv dipped. Then replacing all of the boot floor including the rotten side pannels with chequer plate and bond bolt and rivet the whole lot together.

Any thoughts from anyone better at fabrication than me.