Had a query about the prep for the decals.  I have been sanding and filling the cabinet and backbox for what feels like an eternity.  Finally got nice sharp corners & edges and everything else as smooth as I can get.

I have started with a primer on the backbox and sprayed that then sanded again lightly then sprayed more primer on again.  Do I sand again lightly before putting on the main coat of blue paint? 

Also given that the decals are going to go over the sides and front do I still spray that blue as well or just leave those areas with primer on?  If I do spray them blue do you sand even that final coat lightly before applying the decals?

Any advice would be appreciated.  Cheers