"Demolitions" isn't really an Army MOS, per se. About the closest thing they have are EOD and Combat Engineers. 

Keep in mind, these guys aren't SF. As an Air Cav unit, they'd be grunts in helicopters. Rifles, m60s, grenades and a few guys with M79 grenade launchers.

In the Corps we have the 0351 Assaultman, which is closer to what people think of when they think "demolitions". They breach walls/doors, and employ rockets against enemy armor, but they're generally in the Weapons Platoon of infantry companies. 

EDIT : Anyway, if this looks like it'll take off, I'll bang out a character sheet and whatnot. I love military RPs, and haven't had the pleasure of doing one based in The 'Nam.