1990 Honda Accord Question: I actually have a 1987 Honda - Alternator Bearings

The way to determine which component is at fault is to remove the fanbelts one at a time when checking for a noise .Removing the fan belts stops the alternator from being driven and if the noise you hear goes away when the alternator belt is removed the problem is in the alternator. If the noise is still there the timing cover and valve cover has to be removed to gain access to the water pump.
No one replaces alternator bearings any more as a remanufactured alternator is cheaper, and if replacing the water pump, the timing belt, camshaft seal, crankshaft seal, tensioner and timing belt should be replaced or very carefully inspected.