Malcolm,
The brake fluid issue of not using the correct mineral based fluid is not just a mechanical damage one, but a safety issue primarily as it can effect main or steering brakes, so should be treated with utmost importance. I was involved in repairs to these vehicles for a good many years for the British Army, so well aware of the consequences.
Also, never known of an issue with the throttle wing nut. If there had been any reported occurrences, an Instruction would have been issued.