The tone ring (
E7TZ4B409B) can be removed & replaced with the ring gear installed if the index tooth can be located. It may be obscured by grime, but a sharp pick should hang in the notch enough to ID it. Use a pry bar on the OPPOSITE side to push the tone ring away from the ring gear, working around at least half the circumference. Eventually, the tone ring will slip off, and the tooth can be disengaged. Installation is the reverse.
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