My "new" '74 Duster- or why I need a project like a hole in the head

Sorry I worded that badly. Really what I want is the width of your rear axle, outside side wall to outside side wall, and the same up front. I want my tires to sit in the wheel wells identical to your car. I want to make sure before ordering the custom offset rim$ for my narrowed axle that I've got the back spacing right. Simplist way I can think of insuring that is to match the track width you have. The front isn't a big deal as that is pretty much a known for a 275/35-18 but my rear set up is way out of the norm.

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