I went to the source of all parts information, Brownell's on line catalog, and it shows both Series 70/and Series 80 grip safeties. Some of the makers state that their safeties are for the Series 70 but can be modified for the Series 80. However none seem to state that a non-Series 80 GS will work on a Series 80 after the firing pin safety plunger, spring etc was removed.
I would not know what modifications would be rfequired to a non-Series 80 GS to make it work with a S-80 pistol, either.
The question therefore seems to be, "What is the difference between the two style grip safeties?"
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