I know what you mean. My 1984 has that rack position sensor and my 1985 doesn't, but only because it has a replacement engine (~1982). In the 1985, that nut was so easy w/ a 3/8" socket wrench. In the 1984, I had to keep flipping a box wrench to tediously turn 1/16 each time, unless I resorted to a crow's foot (forgot). You only need to loosen the nut enough to rotate the IP, but loosen enough so you don't risk shearing the gasket seal and causing a bigger head-ache (oil leak). And don't forget the rear bolt, which was also fun. I recall loosening it from below.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans