835 receiver differences - side saddle, minishells

I have a few questions about the Mossberg 835.

-Is there a photo comparison allowing exactly which dimensions of the receiver differ from the standard 500 and 590?

-Is the 835 compatible with side saddle carriers that replace the takedown pin and ejector screw sick as Aridus Industries?

-Is the 835 at least partially compatible with minishells by using an adapter?

I have an 835 that has the potential to be more of a defensive shotgun, and these are some questions that I had.
Thanks