M2 Smoke Discharger?

Howdy Folks!
I posted a similar post in the Armor section recently and I got plenty of help, but I still have many questions. Too many to post probably. lol
Anyway, I just got promoted to Aftermarket, but as stated in a previous forum I read today, Murphy paid a visit to me also, last week. lol So it's time to get some Scratchbuilding/Kitbashing experience. What I need to do is, I need to build some smoke grenade launchers for the Tamiya Bradley M2. I've bought some 1/16" brass tubing, and a larger size (in case I decide to have them loaded and with caps on them)( or else maybe I could use Putty, or a combo) I actually think they might look good empty, I don't know, and I also have the correct gauge styrene to shape the bases out of. I have never seen grenade launchers in person, at least since I was a kid on a visit to the British War Museum, so any help is greatly appreciated!
That's the kind of feedback I'm looking for this time - What you guys would do? (loaded; unloaded, etc.) and which routes you would take in building them? (shaping styrene, cutting tubing, etc.) I have some pics that are very helpful, but the more pics the better, in my opinion, especially close-ups or personal knowledge, which is even best sometimes. Cheers, -Spencer