There are instances in factions that allow this to happen based on their rep and allies. Just make sure it makes sence, maybe do some RP if needed. You cant though put sammies on a bounty hunter vhf....lol
I would consider it unlikely, there's no just the techchart nerfs, now ships themselves can only use certain guns. For example Sabres can no longer use Sammy's because is OP. While according to the techchart a Rogue ID with Sabre and Sammy's would only give you a 90% nerf, because of the ship itself you will now have only 10% or 1%, I forget which.
i dont know what exactly is sammies but my idea is very near than your. for me it was for use the tartarus without to be molly or rogue necessarily. sure with my idea i can hope 10% or 1%. I explain a gladiator with a tartarus mounted and the all who fly under Unioner ID. on the techchart it seem possible but with your explaination sure it's not.