I have a frozen pivot assembly. I needed to remove the pivot tube from the engine and now need to remove the rubber mountings (Item 4 on swivel case diagram) from the engine case. I have taken out the 4 bolts (Item 16) and square cover (Item 6) from each side, but can't pull the rubber mounts out to change the bolts. Any suggestion as to how to pull them out? They have "glued" themselves in the recess.