Crank Seal Leak - 2.25 Petrol 90

Hi all
I have a 1985 2.25 Petrol Land Rover 90 which seems to have developed a Rear Crank Main Seal leak. It was only quite minor to start with so I've been managing with it for a while. However, now it's leaving a small oil puddle even when parked up and I'm having to regularly top up the oil by quite a bit so I think it's telling me to get it sorted!

I've spoken to a local garage that deals pretty much exclusively with Land Rovers. For the new seal to be fitted and a new clutch (may as well get it done while the engine or gearbox is out) they've quoted me around £1900! As I try to avoid using garages as much as possible as I mistrust most I don't know if this is massively excessive or about average?

I'd attempt it myself but I don't have the lift capability to remove the engine which most people seem to do judging by other threads and I'm not sure what the score is with removing the gearbox.

Is there a way to do this with minimal tools and without removing the gearbox or engine completely? Is there a method of separating them enough to carry out the work required? How much needs to be stripped off to do this? Does anyone have a step-by-step guide or a link to one that's easy to follow?

All help appreciated.

You will need to remove the gearbox.
This can be done backwards, off the engine, underneath the car (ie the engine stays in).
It is not for the fient hearted.

The gearbox and transfer box are heavy.
You can sort of support them from above when you have the tunnel and floors removed.

There are several links/videoas ...
Here's one ...