1971 chevelle

[junior55]

have a 1971 chevelle with a lowering kit dont know to much about it bought car this way,it has 20's in rear 18's in the front...All springs on car are red.I wanna lower rear 2" what do i do because will sit level because fronts lower,because I wanna put sum 22's in rear and 20's in front so wheels are shoved up further in the wheel wells.