I had the same thing happen to me it turned out to be the oil sending unit.
It is located right under the Brake Vacuum pump on the passenger side.
Need a mirror and good flashlight to see it. You can feel it out when the car is cool to get an idea.
It was leaking right out of the electrical connector. Also found out that the vacuum pump seals were gone to so I replaced them as well.
I did take pictures of the whole thing I am just having problems loading them to the forum.
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