To access the CB pivot Bolt (I assume by Centerboard seals you are refering to the rubber washers that go on each side of the CB trunk) you reach in through the 2 inspection/bailing ports at the forward end of the cockpit sole. You will need two 3/4" hex wrenches (one should be a ratchet) to tighten the bolt. I'd try tightening the bolt first, although replacing the rubber washers is still a good idea! You wil lneed to completely remove the bolt to install the washer under the head of the bolt, not hard and in fact easier to do than to explain......but best done when you have plenty of patience (might go absolutely smooth, might get slightly hard if CB moves knocking the pivot hole in hte CB out of alignment with the holes in the CB trunk. Obviously, I have done this a few times in the 14 years that I've owned my DS II (I usually remove the CB for thorough cleaning/painting every 2-3 years, just lower partway other years).
One important point, if you do remove the CB or if it should drop out partway while replacing bolt/washers, the CB actually pivots on a plastic bushing NOT the bolt. The bushing is what the pivot bolt actually clamps against, allowing the CB to easily pivot.
My boat is a 1979 model, but had been out of the water for 5 years when I bought her, I don't recall the pivot bolt leaking when I first put her in the water. Are you trailering? Or leaving boat in the water? Sometimes those washers will swell a bit and stop leaking after a few days in the water.
One other thing, are you SURE that the leak is coming from the CB pivot? I had a leak at the hull/deck joint that let in a surprising amount of water during a less than 2-hour sail a few times. The putty that O'Day filled the seam with had chipped out in a few places. I fixed with a flexible sealant.
