The real limiting factor on these trucks is the front end, unless you do a z on the frame, cup the a arms, or go to a full front dropmember you will not drag frame, after you get the front of the truck to the ground then you will have to change the rear, Kieth
If you want a inexpensive drop add 2" spacer block between the trailing arms and the rear end, I got mine from Boris for $60.00 then you will be able to take advantage of your notched frame. Kieth
http://kieth.smugmug.com/Trucks/66-G...8_QhxZCfT-A-LB