I came outside this morning and noticed a puddle underneath the back of my car (W126). I stuck my finger in it and smelled it and lo-and-behold it was diesel fuel. I looked under the back of my car and saw a small little bung or hole (looks like a drain of some sort) dripping onto the ground. I didn't jack my car up yet or anything to get a better look at it but it may be coming from in front of the tank too. Like I said, I can't tell yet but it looks to be coming out of that drain. It doesn't do it while the car is running. I'm at a loss. Any suggestions?

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1963 Ford F100 - Cummins Swap?
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