I must have missed something. What photo are you talking about? By the "gear doors", do you mean the main landing gear? Or something else that I missed?
Yes, I clicked on Deino's link about the 055P or 055R whatever you want to call the 6-1 rebuild of 055,, anyway, there is a detailed history on PAK-FA, and its obvious with the main landing gear doors open that there is NO place for a side bay, as the fuse is covered by the engine nacelles butting up against it, and the nacelles house the engines and mains and that is it,,, NO ROOM for any more toys..
Weapons bays fore and aft are very shallow,,, don't take my word for any of this,,, "run your Kodaks over those pictures",, something my Great Uncle Henry used to say when he wanted me to look at something???