The mustang II cross member I'm going to use in my 59 rambler will only have about 4" of clearance at ride height. Is this enough clearance? The roads here in the Phoenix area are very good, so pot holes and such are not an issue. My concern is the sharp dips that I'll encounter occasionally. I'm going to be using an air ride suspension and I'm not sure how stiff that will be. This is my first hot rod from scratch. so most this is new to me. Also, I have my lower control arms parallel with the bottom of the cross member, and I was wondering how much difference it would make in ride quality to run the arms down a few degrees. I need to get these few problems hammered out before I start to fabricate the frame. Thanks for your help.