I did that but only lasted 2 days.
The main problem is,the wire from the sender on crankshaft.Is old and not long enough.As the vehicle ages the insulation shrinks.What I did was make sure there was slack in that wire going to socket where the Amp screws onto.What happens is the socket pulls away from the amp.
So I used a little super glue gel pulled socket down a little,few drops super glue on socket base.And pushed socket up and held it with channel locks 5 mins.
Now when you screw amp back on,the socket won't be pushed down.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran