Emergency Strobe Installation on 2006 MegaCab

I am going to attempt to install an emergency strobe package in my 2006 MegaCab, but I am having a problem deciding where to install the power supply and fuse block. Somewhere out of the wet/rain but is still fairly accessible. Anybody have any experience installing one of these setups (90w, 6 outlet PS with 4 strobes and 2 grill lights with a single off/on switch) that could point me in the right direction and give me any gotcha's I need to watch out for? Thanks immensely for your help!