You're welcome.
For the dry filtering thing, just make sure that the application o oil is quite light. In fact, it should be so light that the main color seeps through. Oil paints (the one that comes in tubes) are translucent and easy to apply so you should have no problem with that.
But before you do that though, I suggest you give your tank with a medium gray pinwash, leaning towards the darker side. That means, do not wash the entire tank. Just put it along rivets, nooks and crannies. Capilliary action will do the trick. This is to compensate for the preshading color which is not evident...or present...in your model. Also, I've seen pics of Abrams whose edges are a little dark (perhaps due to grime or something).
Oh, by the way, you should add a little decal setting solution to that large decal on the barrel of the gun. It looks like it's silvering.
But overall, it's a very well made model.
Angela
(Phone rings in a taxi company)
Taxi company: "Hello, "
Passenger-to-be: "I'd like a taxi"
Taxi company: "Where do you need the cab?"
Passenger-to-be: "At my home."
Taxi Company: "Where is your home?"
Pasenger-to-be: "I don't give out my address."