What about just finding a TJ getting parted out and cutting out the coil parts? It doesnt seem like you would need to buy a kit if you know how to weld. I have seen TJ frames go for cheap on CL. Any reason that wouldnt work? I figure you could just cut them off the frame and weld the parts onto the YJ frame. Although I have no plans to do a coil over, I have wondered why people dont do that.