The best tool I have found is a bar about 1 1/2 ft long with a knurled thing on the end, you push it over the retainer clip end and pull up. Since it gets the whole tab, you seldom ever pull out of a clip and believe me, it will pull those clips. Those things do show up on ebay from time to time. I also have one as pictured that will work if the guides are not stuck too bad and it does not spring when you whack it.
