Has anyone ever changed the oil in V8S diff

[z_chromozone]

Now I have asked people to try and identify the LSD used on the V8S to no avail. But, after asking around I found someone that recommended EP-90 oil for the unit. However, there is no hole to either drain the thing, or to refill it. Unless I am expected to suck the stuff out the small breather tube on the top. Are these sealed for life, or do you need to find the secret switch to reveal the drain hole.

Any help much appreciated.

Z