[Landseer]

Can you get underneath and read the code on the bottom of the transaxle?
That's the place to start. I'll decode it for you, or somebody else here will by using the tech spec books. You probably want LSD for icy conditions in Norway? Makes a difference.

Its possible to check for LSD by lifting rear of car, turning a rear wheel, and looking for the directional behavior of the opposite wheel. If turn in same direction, LSD.

If you take the back cover off, it can be shown definitively.

Mine upshift well, but grind into the lower gears on downshift. Many of them behave this way on early cars. Theory is that poor clutch maintenance and inferior design of synchronizer arrangement work together to damage the parts. I have one rebuilt early box that is very smooth on downshift, so it is definitely possible to have good performance.