First time user.
I could use a little assistance from some more experienced 300D owners or techs.in trying to track down what the cause of a water leak on the passenger side floor is.
I have checked the body drains and the drains near the hood hinges and they are clear. We brought the car from Florida with us to Mass. and would like to keep it in good shape. The water leaking is causing some rusting and needs to be found. Can anyone provide any advice on where this water is coming from. Are there other drains to check? There is a panel on the inner fender should I remove it and look for the leak there?

1980 Mercedes 300D
1987 BMW 524TD