the truck had alot of rake from the factory, pre-lift measurements were from shop floor to fender 36" in the front and 39 5/8" in the rear. So you add 4.5" to the front equals 40 1/2". Take the 1 1/4 block out of rear to come down to 38 3/8" and add the 4" block to bring the rear up to 42 3/8". That's a 1 7/8" difference.
i ordered the 3 inch block today mine has right at 2 inches of rake after installing the lift so the 3 inch block should bring that down to just under 1 inch
its actually a 6.5 inch lift they sent me the wrong lift and i didnt realize it until i was taking pictures of it for a guy does have the nitro shocks though
new zone 4.5 inch lift for sale 2014-16 silverado or sierra 1500 4x4 with steel suspension, i decided to go with a level kit, asking 1000 the kit was 1200