I have a 29 tudor sedan with a 4" drop front axel coil overs on the rear. I would like to get it lower . What are my options? I am sure I will need to kick up the frame in the rear for starters. Would air bags be the way to go? On the front the buggy spring comes up to the cross member but there is a few inches above the cross member to the bottom of the radiator. Should I change out the cross member to eliminate this gap?