Thank you. Now the car is through its MOT I find the steering just does not feel right - so will change the box over. It looks like an easy enough job.
Steering boxes will have some play, and the trouble is modern MOT stations won't have a clue how to deal with them. Check against another known good car if you can.
Apart from endfloat, have a look at the output shaft while someone is rocking the steering wheel - it is possible to get wear in the bushing down there and that can also give quite a lot of play. Somewhere like steering services in Wimbledon cam install a new bush and ream it to size if needed. Unfortunately that needs the box out.
12 years ago Alice (Rapier IIIa) failed her MOT on play in steering (and front flexible hoses)
I checked the endfloat which was around .015" and so removed a couple of shims it now sits nicely at .006". There is still some play at the steering wheel - but I do not know if this is normal on the Rapier. Because the parts didn't arrive to get her in for a test on Monday I now have time sort this properly. I do have a replacement steering box but if some play is normal I dont want to waist time...or parts.