Yes a flip kit on a blazer, lowers the rear more than on a pickup.
This is kind of a true statement.
I think it just puts the rear axle closer to the frame rails, because the blazer frame is different than the trucks.
It will also put the center section of the rearend really close to the floor.
There are companies now making blazer c-notches.
I recommend this.
http://www.crownsuspension.com/lower...r-c-notch-kit/
A lift shackle would probably work.
I'd like to see the one you bought.
Another option is to run a 4x4 rear spring hanger with your flip kit.
(they are longer than the 2wd version)
But these would have to be found used at a junk yard.
And they are riveted on just like the trucks leaf spring hangers.