Typically there are either two 7mm screws or two Phillips screws mounting the voltage regulator.

The question is corrosion, access and skill level.

If the screws have serious corrosion they can break, forcing alternator removal.

Even if you have access and the required skill level, it is often easier to remove the alternator.

I prefer to remove the alternator for:
* Ease of repair.
* Inspection.
* Cleaning.
* Generic part store testing after installing a regulator to verify function.

7mm screws
PeachPartsWiki: Refreshing the Alternator

Phillips screws
Mercedes Voltage Regulator Install


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