if your blocks been line bored you can buy another seal that has the same sized internal lip but the outter dimension is larger. you'll have to work out how much they carved off to line bore the block & get this new seal milled to match the new centreline. sounds like a lot of work but it's not that bad. any machinist can make this fit for you relatively cheap. it means that this cambelt plate is now custom to your engine. the idler wheel will take up the slack on the belt.