Is it allowed to give them a background... basically an image that will in theory be placing them in a 'box'... It'll not be on top of the ads... It'll be added through CSS [#ah] ..

Ross?

So long as they remain in their intended position (at the top of the page) then positioning a box or container of some kind behind them is fine

Sounds good - you can check it out on the link I gave in the other thread [skin is on my account]

That's not exactly what I thought you originally meant, but the way you have done it is absolutely fine. Quite inventive really

Cheers!