I read this on the tech links... "Height is a big issue with spring overs. The most common question is, “I forked down $1,600 for an Old Man Emu suspension kit (or some other lift kit), can I still use it?” Yes, you can, but for every inch of lift you have, add another 5-6” for the conversion to it. So if you have 2.5” lift springs, you are going to have about an 8.5” lift, which is tall, more than tall enough to run 37’s on any Land Cruiser. General folk lore is that a SOA on somewhat flat, stock springs will easily allow you to run 35" tires. In some cases, you can even run 37” tires with a SOA with stock springs." The article says 2.5" lift springs...so My question is this, how much of a "lift spring" would a '97 F150 leaf spring be over a stock 40 spring? Does that make sense? how can you or do you measure how much lift one spring will have as opposed to another? ???