OK it looks like the N52 uses a different tool kit than N53 N54 etc. I'm guessing that the inside lip for the seal probably goes completely around so "rocking" it out by pushing the side of the seal that doesn't have the lip behind it doesn't work. It looks like there is a tool available that puts screws into the seal to pull it out but the one I ordered got cancelled and the other makers/suppliers don't show the puller/installer disc in the picture of the tool so pretty weird. I think I'm just going to wing it without special tools but if anyone one has some input still much appreciated! Cheers!
