Dual wheel options

[78customdeluxe]

Im tryin to dress my truck up a little bit. Just as a little background to what i have done to it. I have added amber lights all over the bottom edge of the fenders, cab, and bed. running boards, bedrails, homemade headache rack, and other little things, its a 1982 K-20 6.2 diesel. Its my main towing vehicle so i cant really lift it much because my dmi bumper is already too tall. I dont wanna cut holes in my bed when i end up puttin stacks on it and i dont wanna have them stickin out too far on the side like i know they will be, so the next step is to put duals on the back. I think i have two choices, put on a dually rear axel or get dually wheel adaptors. I want to go for the second option because i know duallys suck during the winter and if i wanted to i could just make it singles easily, plus my current axel has a locker in it and is semi floating and im 99 percent sure it wont go in a ff. i have never looked that closely at a dually rear axel, so do they from the factor have spacers and how wide are they? if i knew that then i would know if i could just go to the junkyard and get some, or would i be able to double them up and still have them work decent? im just throwin stuff out thinking while typing so thanks for bearin with me with the long post.