Take a 17 mm high quality open end wrench. Be careful in your placement on the fitting. It takes a good amount of force to loosten them and tighten them. Once you get the hang of it it is not too hard. You will have to loosten the little brace brackets to get them off the injectors and the pump, and I usually can loosten them and remove them all still fastened together.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.