I'd check your diff oils asap too.
You need to drive it to get the oils warm not just the engine.
That oil looks awful. I would be tempted to refill and run it good and hot and...
If you want to extend the pipework it's 6mm OD nylon, available from eBay or your local pneumatic place.
Defender axle breathers...
Breathers, don't blank them.
I've got one of these, been in the family at least 40 yrs. Awesome thing. Not cheap to buy now though secondhand. Library pic not mine. Mine is...
Make sure the fill plug can be undone before draining.
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