Thank you again Mr Toad
It occurs to me (not yet having taught myself the workings of a JCB) that perhaps the hydraulic pump for the rams may be driven from the gearbox. If that is the case, I am wondering if the hydraulic system will be “charged” when we tow it ?
In regard to your comment, I am delighted that such an evidently knowledgeable fellow sees this as “an interesting challenge”! Especially as when I eventually get it home & start trying to restore it, I have little doubt that I may have further questions. Assuming that this is ok with you.?
Best regards.

Mark, May 2009

Hello again!
The hydraulic pump is driven by a short shaft from the front of the engine crankshaft. The main hydraulic pump is situated just ahead of the radiator. The pump for the hydrostatic steering is mounted on the front RHS. of the engine, driven by the timing gears. Thus, engine not running = no hydraulic power.
You are welcome to ask more questions, but Mr. Toad speaks only from personal experiences, and doesn't claim to be an expert!

Mr. Toad, May 2009