Hold up, you said this:
Are you sure you don't have the self leveling option? I believe it was available, as an option, on the ZW7 suspension and came part of Autoride. If it dropped a certain amount but then went back up after driving it, then it's filling up and raising the rear. The same thing happened to me when I first lowered it(I have Autoride). I installed the springs, it dropped quite a bit, then I started the engine and the back end lifted back up to stock height. Look for sensors and small rods connected to the upper trailing arm. It will look like this...
http://i198.photobucket.com/albums/aa136/xxjxaxyxx/IMG_0507.jpg
Some lowering kits sold for Autoride equipped trucks will come with shorter sensor rods or instructions on how to bend or shorten them to accomodate the lower ride height. But, if you ordered a kit for non Autoride then it's likely it didn't come with them because the self leveling option is really, really rare unless it came with Autoride. If your truck has Autoride, or ZW7 along with the Self Leveling Option, everything you're finding while trying to lower it is making sense.
Most likely, your fix is going to be to leave the spacer out, use your original shocks and shorten the sensor rods on both sides.
...It dropped it an in inch in the shop but after I drove it home it was back up an inch where it was before I pulled the spacer out. I have already tried running the Belltech shocks and it dropped it way too much with the spacer in there...
Are you sure you don't have the self leveling option? I believe it was available, as an option, on the ZW7 suspension and came part of Autoride. If it dropped a certain amount but then went back up after driving it, then it's filling up and raising the rear. The same thing happened to me when I first lowered it(I have Autoride). I installed the springs, it dropped quite a bit, then I started the engine and the back end lifted back up to stock height. Look for sensors and small rods connected to the upper trailing arm. It will look like this...
http://i198.photobucket.com/albums/aa136/xxjxaxyxx/IMG_0507.jpg
Some lowering kits sold for Autoride equipped trucks will come with shorter sensor rods or instructions on how to bend or shorten them to accomodate the lower ride height. But, if you ordered a kit for non Autoride then it's likely it didn't come with them because the self leveling option is really, really rare unless it came with Autoride. If your truck has Autoride, or ZW7 along with the Self Leveling Option, everything you're finding while trying to lower it is making sense.
Most likely, your fix is going to be to leave the spacer out, use your original shocks and shorten the sensor rods on both sides.