Toilet tank bolt and rubber gasket

Hi,
One of the 3 bolts that hold the toilet tank to the bowl has a occasional slight drip. I see that the rubber gasket under the bolt head is pretty much shot. I want to replace all 3 bolts and rubber gaskets one at a time without taking off the toilet tank. Do you think that this would work without any leaks especially the large gasket where the toilet tank and bowl meet?
Thanks in advance.

nope, water will gush out of the hole once you remove the bolt. Normally, it is fairly easy to prevent that...turn off the water, flush the toilet holding the lever until all that can flow out, does, then take a sponge and get rid of the rest. Then remove and replace with new. If the bolts are brass, they're probably fine and don't need to be replaced, just the rubber washer.

Thanks Jim for your reply. Would you think that if I only changed the rubber gasket on the one leaky bolt and left the other two that dont leak alone that maybe after I turn on the water one of the other two may begin leaking?
Thanks again

It'll only take a few minutes longer to do them all. Likelyhood is they were all installed at the same time, sitting in the same situation, it is likley the others will leak soon, too. The act of loosening them could cause the others to leak, too.

It's best to tighten and loosen them all a little at a time, keeping things even. One other thing to check, while the bolt is out, rub your finger around under where the washer was and see if it is smooth. If it isn't take a piece of sandpaper and lightly smooth things a little, otherwise, that by itself can result in a leak.

leak

The bolts usually start leaking because the large center gasket is deteriorated and allowing the tank to settle, which loosens the bolts. Replace all the washers AND the large center one.