Thanks James.
I'm a little undecided on what to do with mine but if there's a cheap one on flea-bay or somewhere I might get it as backup. Problem is, the guys who owned the place I borrowed the ramp, transmission jack etc. off last time have retired and there is nowhere I now have access to that kind of kit.
I don't mind lowering the gearbox down on the drive but I'm not taking it out without a proper transmission jack etc. I just don't have the skill. I did have a look earlier before it got dark. I reckon it'd be pretty tight under there even with the gearbox lowered all the way on a trolley jack because of the depth of the transmission tunnel. I might (just) be able to wriggle the remote control housing off but a replacement one is about £150 (assuming RAVE is correct and it cannot be fixed). On the other hand if it is the gearbox itself I won't find out short of taking it off and apart and I don't have the kit for that. A replacement box is £250. Unbelievable! Not much less than the remote control box.
One of those days I wish I had a bigger house, with a big garage (heated), tools etc. Too late for Euromillions tonight. I'll just have to go for the National Lottery tomorrow and hope my luck changes!