As title really!

Back in the Cosworth world after years away, and I don't know what rear diff the car has to be honest, but I do know the LSD, if it even has one, is crap, lol.

I would like to find out if it's a 7 or 7.5 so I know what to change this either open or knackered LSD with!

I know the differences aren't huge, but they do look different externally, but exactly the differences I don't know, and searching has found nothing.

Thanks in advance.