Spot on! Thank you Gino - looks like the original Revell parts will need a bit of trimming to correct, and lining everything up without the location holes will be fun, but it still seems "do-able".
Time go shopping. I've seen a 175th AHC gunship in the Vietnam hueys thread on this site that I have to try (19 shot rocket pods and miniguns). I think the cobra company upgrade set will sort all the weapons.
Thanks for the help,
Matt