Jason- I was in the same shoes as you last summer, I thought it would be awesome to do a SAS so I bought a Fabritech conversion kit and it is sitting in my closet. I just don't have the time and money to do one know and I'm going to wait till I get a job over the summer and start collecting parts for it and do it right.
But IMO, there's no way you can do a legit, not half assed SAS for the same price as what a 6" kit would be, there just wouldn't be any way. Wait it out, get a 6" be happy being lifted for awhile and then do a SAS later on down the road. I think you'll be much happier that way.