1968 Wheel and tire size combination
 

The wheels and tires that came on my car when I bought it are way to big/wide. 20" rims on the rear, 18" on the front. The offset is too deep and the wheel/tires are too tall to lower the car. I am in the process of putting a new rearend under it and I would like to lower it at the same time. Can someone suggest a good wheel size, front and rear that has worked for you? I would prefer something bigger than a 15", and I would like an offset that will allow me to lower it. Thank you for your help!