You are absolutly right, there is no problem at all in enlarging the hud in the default CSim/F18 as you describe and I apologise for not explaining my problem in full. I hope no one was misled in any way.
That's okay. There was always the chance that the problem wasn't with the default FA-18. Now we know. ;)

I want to use the weapon hud in my helicopters such as Alphasim Apache another company Huey etc. I can't however resize the hud in the same way.
Wouldn't the size of the HUD need to be edited in the [VCockpitXX] entry in the panel.cfg for them, rather than the CSWeapon.xml? Seeing as I don't own them and can't try it myself, I'm only guessing.

Mark