Yup, you nailed the site, and it is a great resource.
I know in the past that I have added a clear wash tinted with any color in my pallet. This would be good for an overall wash, but the gradient affect might not look right doing this, but then again I have never tried it. I would think that a coat of future over your base coat, and then a tinting wash would look ok, but to win a show........you might have to invest in an airbrush. I don't know about Ireland, but here in the States, Testors makes an OK starter airbrush kit that's not to expensive. I can't imagine you wouldn't be able to pick one up from a mail order place.