This is just a thought. From what I remember about the frame on my 57 before having the chevelle clip installed was that it's rails were straight in the front. If you want to keep the straight axle why cant you just move it back on your frame and then just cut off the excess from the front? This would save you having to piece together a cut frame. If you want mdern suspension you could do the same thing with a front clip or one of the MII kits. Just a thought.