If there is NO travel that means that the suspension is locked and in total bind. This is possible but uncommon. If you're standing on the crossmember that leads me to believe that the engine is out of the car. That would mean that the springs and shocks are topped out. Your position in the center of the car is spreading the load low and even to both springs. Basically, don't sweat it.
Coilover shocks allow you to make small adjustments to ride height, usually about 3/4" max in the front. More than that and you are out of the shocks 'sweet spot' in the center of the travel range. The benefit of this type of suspension is not ride height adjustment but spring tension adjustment.
Whatever parts you decide to go with, they should be suited to the job they will be required to do. If the car is going to be mostly a cruiser with the occaisional onramp/backroad rip then a coil spring suspension will work fine when paired with a good set of adjustable shocks. If you want to get a little more aggressive, then consider going to coilovers.
Obviously we also offer a complete replacement clip with modern geometry which is a big improvement. Depending on how in depth your build is going and what other goals you may have they can sometimes be more cost effective. Sometimes some bolt-on parts are best for your build and will pay dividends.
Take the time to click and read this article: "
Coil-Over Conversions Explained." It goes in depth about the different front options available and applies to your Camaro.