heres my 870 "club" with streamlight attached and my M-2 BENELLI with streamlight attached.
as far as zoomy parts for the benellis and remington 870's, DAVES METAL WERKS. this guy does a lot of 3-gun shotguns.
but i like versatile snotguns. both of mine i can grab long barrels and make into bird guns, slap a round limiter in and be legal beagle for dove or quail.
the main mods i suggest on any of them are:
1) chrome silicone mag tube springs
2) OVERSIZE SAFETY for gloved hands
3) aluminum mag tube follower
4) picatinny rail for any optics or lazar(laser) beam death rays
5) 18" riot barrel
6) 30" bird barrel w/complete choke kit
7) a VANG COMP JOB.........YOU WILL thank me,evident by those 100yd slug groups i showed. my bird shot patterns improved greatly after taking mine in to him.
8) molle type scabbard case very very handy for humping. 18" barrels only.