Yes, you need to get the car as high as possible. Jack stands will typically get it higher than ramps. I have both, so I drove front end up on ramps, lifted rear of car with a jack centered under the differential (there is no reason you can't do this) and support the body in the rear with jack stands. You will need a good 6 inches more drop off the rear axle than full sag will provide. You need to support rear axle with the jack, remove panhard bar, remove the lower end of the shocks, remove the rear brake lines from the body as a precaution and lower the rear end till you can remove the over axle pipes. This is the same procedure needed to remove the rear coil springs.
2011 GT Coupe Premium, Black exterior with Charcoal black turned leather interior. Rapid spec 400A with 6-speed MT, 3.73 limited slip axle, 19" painted aluminum wheels, HID headlamps, comfort package. FRPP tune with K&N air filter. FRPP Touring axle back exhaust with Borla 2 3/4" over axle pipes. ST Suspensions coilovers w/GT500 mounts. Spohn poly/del sphere adjustable lower control arms and Spohn adjustable panhard bar with Steeda panhard bar brace. Hotchkis Sport sway bars.