Hi Steve
Looks like you've done all that needs doing in the rear axle. As for the lid, the draft control mechanism may need some adjusting or refurbishing, depending on what kind of life your tractor has led. Draft control on the NP Super is double acting, not single acting as on the Super ie the plough is not just lifted automatically if the top link experiences compression, but is also lowered if the top link experiences a stretching force. A (crude!) way of testing these is to use a crow bar on the top link bracket to replicate these forces - the lift arms should raise or lower accordingly when you apply leverage. However, while you have the lid off, the proper measurements and adjustments can be made on the linkages found inside the lid to ensure proper functioning in position and Qualicontrol.
I am lucky enough to have access to a local expert who worked on Majors during the sixties. Brian is semi-retired and works one day a week for Ernest Doe in Marlesford, Suffolk. Brian made all of the adjustments and refurbed a couple of pins that had worn - the knock-off pin was one. For this reason I have no first-hand experience of doing this. However, the necessary info, tolerances, etc are available in the official repair manual, though you do need a spacer tool made specially for the job, which Brian has and I don't. It's only a question of how wide the tool is though, so replicating would be straightforward. If you need me to, I'll try and get Brian to let me have this info, though he may think I'm being a bit cheeky!
Best
Adrian