good morning,
I had a similar problem,the newer,longer screws are not threaded enough to cut down,when I found some of the right length for mine I then discovered that quite a few of the threads were stripped in the hub,this prob was compounded by there not being enough meat around the hole to retap to a larger size,there is a company on ebay that sells a avm service kit with gaskets and screws cheaply but avoid them as they are rubbish quality(the gaskets are dissolved by oil!)
I found a company in greenford who sell brand new brazilian made avm's at about £140 a pair walk in price, from all the trouble with the old ones I wish I had bought new at the start,
atb and good luck,
ryn