1) You just rotate the ring - don't bend anything...I find that I need to move around the ring and alternate where I hit the ring to distribute the abuse.
2) Reuse the gasket/ring (I don't knwo where you get a new one from without paying through the ass)
3) Nothing required here; if there was water there your rear seat would always be saturated.
4) Try not to smoke or use a welder!
