Kappie,
I started scratch-building the Yorkie some while ago and by the time Model Slipway had produced the kit I was halfway finished. Two years ago I passed the original shipyard GA and Lines Plans to (I think) a3nige on this forum and one other. If you can track them down they will have everything you need.
I still have a United Towing ship spec which shows a small GA plus a couple of photos. You are welcome to copies of these.
Barry M