lifting my 1/2 ton questons

hi i have a 1993 gmc 1500.i have a 3 inch body lift on now. what i would like to do is lift it more. i dont want to do a full suspention on this truck. if i buy a torsion key kit for the front IFS and do a add a leaf and the air bags, would i be able to lift it with with blocks under the rear axle and still lift the front again for maybe 3 inches. i would like 6 inchs more than i got now. i dont want to do anything unsafe.and i dont remeber anything other than the key kit for the front.
thank you