Does anyone know the size of the short threaded metal dowel that the battery holddown plate fits over. This is missing on my car (88 300ce) & I've been unable to find the right size to screw into the vacant hole. The dealer didn't have it as a listed part. Thanks.

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87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)