Just a heads up from experience. I had installed a set of 1 1/4" coils spacers, and sandwiched it between two isolators. Didn't work out too well.

I don't know if when it happened, it might have been when the tierod end on my trackbar was bent, or what. The spacer was smashed/mushroomed, and moved out of place slightly. I don't think it would have happened if it had been against the metal, and not a soft rubber isolator.

I'll eventually get a set of 4.5" springs since I now have a 1 3/4" spacer, and one isolator on top of my 3" coils.

BTW, I'm getting faster each time I drop the front differential. I had both coils springs out, and new spacers installed, and everything put back together in an hour.