Leaky Diff

[pdevonp1]

Hi, I was just about to go for a drive today when I noticed some oil on the garage floor, closer inspection revealed that oil appears to be coming from the right hand side of the diff. I'm guessing the output seal needs to be replaced.

Has anyone replaced the seal before or is it a job for the professionals?

Does anyone have any ideas why this might happen or what else might be causing the leak?

Thanks for any help you can give.
Peter