So, in case I ever finish my Necron army, I'll probbly get Dark Imperium and start a Raven Guard Primaris army. Been looking into this for a while now and here are two things I couldn't figure out yet on my own:

The Primaris models in Dark Imperium come with only one weapon type, and it isn't always the one I'd like to use. 1. Considering that the different weapon options don't look too different, would anybody mind if I say "My Intercessors use Auto Bolt Rifles, even if - strictly speaking - the model have the regular Bolt Rifles."? 2. If I could get my hand on some spare Auto Bolt Rifles from the Intercessor box, could I use them for the Dark Imperium Intercessors, or are the models completly different?

Also: 3. Are the Primaris models from Dark Imperium compatible with any of Ravenguard upgrade bits (heads, shoulder pads...) from Forgeworld?