I have a JMW 10 3D tonearm that has a 180g counter weight. I'm trying to replace it will a 120g counterweight because my cart is too light (7 grams).  I can get the 180g off no problem but I can't get the 120g on. Do you have any suggestions to get it on? I don't want ti break the tonearm.  Lubrication, gently sanding hole with fine grit sand paper , gently heating the weight up? I bought the counterweight at music direct. It's an official vpi product.   Thanks.