Hey Tom, I am also in the process of planning a huey diorama (with a PBR too). While not a veteran of Vietnam by any means, I've done some poking around on different websites, mainly those created by veterans'. The number of hours varied a lot from what I can determine: some gunships were downed within one or two missions while others flew hundreds of hours before being retired. In terms of logos, slogans, personal pictures, etc. on the ships the sky's the limit if you're not going for a particular ship or unit. Check out some Seawolf sites and the like, etc., etc. A very good resource is the 174th AHC site, although I can't seem to access it at the moment (odd?). Their Dolphins and Sharks ships are great.