Not to be a wet blanket...but
Certainly go for the easy and most obvious. But it may go further. I had a similar issue and did the wire, the fresh water inlet, the stanchions, and several other things.
I knew the port lights should be rebedded. Though I was still getting water forward. I was tired of trying to fix. So moved on and rebedded them. Turned out the rain was getting in around the port lights, and slowly soaking it's way forward all the way to the forward stateroom. I had posted the issue, and a kind forum person made the comment the I may have to broaden the search . Frankly I poo pooed it......BUT I was the poo.
It is amazing how far the water can work it's way through the deck.
Good luck, with diligence and trial and error you can get them. Even if they are not the immediate simple ones.