Late follow-up.
1. I noticed that the bonnet spring bracket was slightly tilted at the base, so that the spring was backward and the pin forward. I reversed this ( losing a cup washer into space in the process) and now both spring and pin are vertical. Did not see this possibilty earlier.
2. I unbolted the rear mount crosspiece form the frame, jacked up the gearbox, and found everything had slid rearward about 1/4 inch, maybe more. It looked tricky to extract the piece so I ground away with it in place until I could get a clear drop into the bolt holes. Then a longer bolt, and a tough flat washer to spread the load and be sure the lock washer had something to bite into, and a good yank on the wrench.
Does any one have experienced of removing that crosspiece without removing the drivetrain? It looks as though it would foul up on the overdrive. I would really like to replace it with a new one and better drilled holes!
any way, I am much happier with both changes. One day soon i shall venture to start the engine after its long dormancy.