CLR will make short work of the corrosion, and make the holder look like New again. Use a q-tip dipped in clr, and swab the holder, and remember to rinse it off again with clean water. You need to neutralize the battery leakage, or it may spread to the rest of the board. You can also use white vinigar and water to neutralize the leakage, but it won't clean the holder like CLR. CLR is cheap and to see how good it works, put a corroded part in a cup and submerge it in clr and watch the corrosion bubble away. Of course if the holder is bad, the best thing to do is replace it. I do vote to install a remote holder and get the batteries off the board, that way if it happens again you can just throw the holder away and get a new one. Another tip is to put the remote holder in a plastics Ziploc bag so leaking batteries will only leak in the bag and nothing else. I quot buying energizer batteries, because I had multiple batteries leak in the packages before they were even opened. The Nvram is also a great idea, but can get expensive if you have a lot of pins.