I watch ebay for stuff like this quite often, and I don't recall seeing a completed conv with sedan side walls and everything operating properly---not to say it can't be done--- but I have seen several failed project cars with them. Going cheap is not always the cheapest way to go, just something to think about. You also need to keep resale value in mind, and a new set of conv side walls will more than pay for themselves IMO. I have never had a need or desire to try it, so I could be wrong, especially if you are a metal shaper.