Lowering van

i have a 1980 dodge b200 van. I've been working on it for a while now and have done a motor swap for a 440 lil 31 wasnt cuting it. on to the question i want to lower the van but have no clue how to do it. they dont make kits as far as i know.i want to go like around 3 ins down. any help would be greatly accepted