MRR1999 - We never tested 3” drop coil springs on a full weighted (with cast-iron heads) big block first gen Camaro.
If you’re running a big block first gen Camaro with aluminum heads you could use the 3” drop small block coil springs. As far as being level, every car is a little different depending on A/C, automatic or manual trans, steel of fiberglass hood, battery in front or trunk, overall tire diameter, etc. We typically get level ride height with 3” front springs and 3” leaf springs, but like we stated there are many factors to being completely level.
Here’s a photo of a 3” drop front and rear:
