When I cut my coils in June, I measured around the outside circumference to see what the circumference was. All the research I could find was 1/3 of a coil was about 3/8" and 1/2 a coil was closer to 3/4". My circumference was right at 18" so I figured 6" around was 1/3 of a coil, 9" around was half of a coil. I cut mine 7.5" around. For my rear, I cut right at 1 coil.
I'll post a couple of pics so you get an idea. Sorry about the first few pics, had a broken lenses on my phone and it's the only angle I have pics in all 4 states.
Before Installation
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Un-altered BT Kit
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Modified Coils
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Spring Scrap
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With Cut coils and on 275/55-20- I did pick up 1/2" in fender gap with the drop in tire size, but the body also sits 1/2" lower.
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