Erm I unlocked the bottom ring with the tool and wound that to the desired height then wound the spring down to that level then locked them together twisting the rings the opposite way , if that makes sense ;) like I say it's possible to go so low that it wouldn't be drivable this might differ to the gt though. For what it's worth I've only had 1 set of coilovers on the glanza as it's my first and I havnt had it long, but all but 1 of my previous cars I've had coilovers and I must admit the BC's have been the best quality so far ;) but I havnt tried any other brand so I wouldn't know any different. Dale.