My son (who is highly mechanically inclined but awfully impatient at times) has undertaken to replace the ball joints on his '89 blazer -- a project which neither he nor I knows the first thing about. So far, it isn't going well. He has pounded on the top spindle of the ball joint ad nausem without it so much as moving. He purchased a tool (a "fork") that was supposed to help get it out, but still, no joy. Is there some tried and true method for doing this that he is overlooking, or is this the reason they charge an arm and leg for doing this? TIA for any suggestions.