Yes the replacement should be a direct fit. Since it's probably from a salvage yard, try to see if they'll let you apply 12V to the fan motor before you buy it. The squirrel cage (fan wheel) has small metal clips added to the perimeter for balancing purposes...you'd like to know whether the wheel is in decent balance before buying the fan - and it probably is unless there are signs of damage elsewhere.
8D2 820 021 is the VW part number. Other letters/numbers on the label are just mfg data.