Further progress. Tony cut the 2" x 16 tpi thread on the Gland Boss on the Water Pump.
Not a straight forward exercise where he would have preferred to have used an ordinary straight external thread cutting tool, but the thread is half buried within the casting and the Bolting Flange for the elbow sticks out too far and would have been in the way for a direct approach at the thread in any case.
So to overcome these difficulties, he ran the lathe in reverse and used the same internal cutting tool that he used to cut the thread in the nut, but on the far side of the tool post. This worked just fine and the nut screws on comfortably.