Ah Gordon! I'm afraid what you have just described when turning the steering at the wheel on axle stands or a lift is normal and is caused by the complicated routing of the steering shafts. You can lessen this effect by making sure that the steering rack damper has been serviced. there is a nylon type element as part of this which should sit freely in the adjoining component part and will need sanding slightly to again move freely. I have as have others posted here previously on how to do this. It's located under that tab locked 1" nut that sits close to the pinion gear of the rack.
Many racks were never lubricated correctly on fitting at the factory, just with the limited protective grease coating to the rack and pinion elements whereas it need to be quite full of a slumping grease. In my post on this I explain how to inject 100mls into each end of the rack and then to reinstall both end dust covers again mostly filled with the slumping grease. Take note of the correct positioning of these end covers as the rack element of the steering rack extends into these and if pushed onto the rack too far will be damaged/punctured by the rack if a full lock is applied on either lock.
This will greatly smooth the racks movement but you will not totally remove that sense of pulsing however the movement you have mentioned and the interference are another issue that is not caused by this. I too struggled with this as our last Morgan had a steering box and didn't have this phenomenon.
If you disconnect the rack from the steering shafts the rack moves smoothly when actuated at the road wheel. Un lubricated it really can present as a push/pull feel like something is binding.
