My brother is looking at buying an '86 K30 ex-military truck. The truck has rust around all the fenders but the odometer only reads 20,000 with the 6.2 non-turbo diesel. He is looking at lifting the truck and trimming the fenders, since they are already rusty, for bigger tires probably around 37 inch. Can he get away with a 4" lift with the fender trimming or is a 6" lift needed. What is the cheapest way to lift it the necessary height, no blocks, i read something about the rear springs in the front and shackles. Can someone give me some more info on this. Thanks.