Question about shackles

I have been building a TJ for the last four years so I am some what new to the rear leaf spring world. My question is this> When RE or Rustys say that have 1 1/2 longer shackles does it lift the jeep that much or someone told me only half that height (3/4) any help appreciated.

I believe they list their units by how high it will lift your vehicle. Just call them to make sure. But yes, if the schackle is 2" longer then you will only get ~1" of lift.

rthill97tj, you are correct about the RE shackles. They are 1.5" longer than stock and as they only lift the rear, result in a 3/4" lift.
Now, if you look at RRO they list 1.5" shackles that actually lift it 1.5". You guessed it; they are 3" longer than stock.
HTH