@ramrod thanks for the explainer. I'd just had my second shot of Pfizer vaccine when I read your reply, and wasn't really thinking clearly, so it wasn't your explanation that was fuzzy - it was my brain!
Poor old Gertrude....
So I finally got Gertrude on a ramp this morning. It was not a happy experience.
Overdrive
The overdrive relay under the dash has been removed, the solenoid wiring appears to have been pulled off (ie, there's only a small tail with a bit of insulating tape attached to the solenoid), so I'm suspecting that everything needs replaced.
Suspension
The front nearside damper is in a bad way, one of the steering rack boots has split, and the ARB bushes and links are badly degraded so the anti roll bar is rattling (the nearside bush is totally destroyed, which possibly relates to the bad damper putting additional load on the ARB).
Drivetrain
The centre bushing is pretty tired (this explains the slight vibration between 65km/h and 75km/h.
So what should I do? She's never going to be a trailer queen, so any money I spend is essentially 'dead money', but I wouldn't feel right selling her to somebody as is, and also need wheels to keep travelling.
Is it worth putting a second hand pair of dampers and ARB + links on her? Or am I just inviting more heartbreak?
If it's viable to use 2nd hand parts, does anybody have these parts and are willing to part with them for reasonable money? ;-)