Ok, I have these too. I finally decided on leaving it at 1.5 inches lower all the way around. I measured from ground to fender lip. For me, each wheel is roughly about 24.5 inches from ground to fender lip. I did the install myself, wasn't hard at all. If you follow the instructions, the height is not even close to what TRD
recommends. I've since tweaked it myself and gotten an alignment done.
Also, in the process of tweaking it, I mistakenly lowered the rear height to two inches lower, and that was a mistake. I could hear squeaking coming from back there every time I hit a bump. I guess I was hitting the bumpstop.
What you need to do is adjust them yourself, and here's the process I did:
1) Loosen the tightening screw with a 5mm hex wrench.
2) Make a dot on the lower spring support with a dark permanent marker (for identification purposes when adjusting height)
3) Each FULL turn of the lower spring support equates to a height change of 1/16 of an inch.
4) I THINK you need to turn the support COUNTER-CLOCKWISE to lower it. You want to move the support LOWER down the strut assembly towards the ground.
5) Count the number of times you see your dot pass. That equals one full turn. To lower it a half inch more, you'll need 8 full turns all around.
6) When you're finished, tighten the locking screw with the 5mm hex wrench.
If you wait until tomorrow, I'll go out to my car and I'll be able to tell you how many threads I have extra, and you can match it. Hope I helped you!!