[JLMounce]

Where are you measuring ride height from? Measuring points at the frame is best, sheet metal isn't always hung exactly, even from the factory.

Hybrid coil-overs don't require frame modification. There are some true coil over systems that don't either, but those typically use the upper shock mount for the top mounting of the coil over. That part isn't designed to carry the weight of the car, only shock forces. The coil-over conversion I like the best because of that is the SpeedTech Performance Chicane kit. It cuts out the top of the spring pocket and you weld in a new double sheer mount. Cost is actually about the same as the higher end hybrid coil-overs, but you get the benefits of a true coil-over. These will also work with any of the aftermarket lowers as it uses a T-Bar lower mount with a spherical eye upper mount. The shock is actually longer as a result as well which gives you more compression travel. This allows you to run a softer spring to achieve the same wheel rates, but keeps ride quality better.