one thing to consider with the 53 COE is the front end is pretty narrow compared to any newer chassis.
What this means is if you use a newer chassis the front axle and wheels will be a good bit to wide.
Also, I hope you use some real tires, about 9R22.5", an AD COE just looks silly with 16 or 19.5 wheels.
Front axles can be narrowed, but to make it easier it bolt back in it would be helpful if you used the original frame (already narrow). If you narrow a front axle to fit, but try to put it back on the new (wide) frame it will create a whole bunch of other problems to solve.
Grigg
