I have a '53 Chevy p/u that I have purchased a TCI Mustang II IFS front and four bar rear airbag suspension for, and am planning on ordering a Currie 9" rearend. Currie's website explains what measurements need to be provided when ordering, but I need to know exactly how to arrive at these measurements. I suspect I need to have my wheels and tires on hand in order to get these measurements (?), and I don't want to order a rearend more than once! Any advice anyone can give me would be greatly appreciated. Thanks in advance.