What size wheel and tire do I need? 2.5"/4" drop

[Hazieview]

Hey guys I have researched numerous pages on which wheel and tire size I need but I just can't figure out what will actually fit.

My truck has a 2.5"/4" Drop.
I would like to put Center Line Smoothies on my truck.

I dont like the more tire than wheel look. I dont want there to be a big gap in between the tire and wheel well like I have now with my 15's with 295/50/15s on it. I also dont want too much tire and not enough wheel either.

So I'm looking for that even balance to where my wheel and tire match even out and to where the top of my tire stops right at the edge of the fender when your looking at it from the side.

SO..... I I'm look at going with the 18" wheel size however I do not know what backspacing or width I need or what tire size. I dont want it to rub and I dont want to spend a bunch of money on tires that dont fit....

Can anyone help me out I know these are the style wheels I want with the wheel painted black and the 'lip' polished aluminum like a beaty ring...
http://www.summitracing.com/parts/CLL-5298806550/


Thanks guys!