Replacing or placing a tap into a wingback in the wall:
To begin you will need to measure the rough distance from the inside of the wingback internal female thread and the outer wall plus about three-quarters of an inch (20 mm) to go into the female end of the tap such as a laundry, kitchen or bath tap. The brass tube you need to join these two points together is called nippling brass or threaded tubing. It comes in two common sizes. ½-inch (15 mm) for kitchen and laundry taps and ¾-inch (20 mm) for bath taps. With the existing tap wound out anticlockwise you may find the old nippling brass stayed threaded into the wall bound wingback. In this case simply tease out a length of hemp from your wrist to your elbow and wind clockwise onto the protruding nippling brass and wind the new tap into position with a screwdriver inserted inside the outlet of the tap.
However if you have to work between the wingback in the wall and the new tap. Simply take the section of threaded brass tube and wind it into the wingback all the way then back off one and a half turns back out. Then mark with a mini hacksaw the next cut allowing about ¾-inch (20 mm) to go into the back of the female thread of the new tap. Then remove and finish this cut. Either use hemp (old school) or plumbers PTFE tape and wind the threaded brass tube into the back of the tap and tighten by lying the tap down on the ground and placing your foot on it doing the tube up with a pair of pump pliers. Then insert this section of tube into the wall and up against the female wingback where you will be able to tighten it up till it is in its normal position against the wall.
Note: Hemp is more forgiving than tape as nine times out of ten if there is a leak it will continue to swell and take up the leak whereas with tape you do not get a second chance at all unless you can get another turn out of it which is not likely in these situations.