How big of a job is it to change out a fuel injector on a 280se 4.5? I have an injector that seems to be leaking at the electrical connection. While I was at it I thought I would replace all of the upper(attached to fuel line) hoses, and the lower(under the bracket)rubber rings. I noticed 6 of my injectors upper hoses are held on by an upper and lower clamp, while 2 of my injectors only have an upper clamp; and, seems to be attached to the injectors at the lower potion of the upper hose.