Is the in line sensor you mention threaded into a bung on a steel pipe somewhere in your coolant system? If so, why not just install the proper Ford sensor in the already existing threaded bung?
Wrong threads? Find the proper adapter and this sounds like a easy fix.
Of course, your particular situation may not be as I picture it to be.
More details on your in-line sensor would help us provide a possibly more correct solution.
Larry
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