Is it possible to overtighten or damage injectors? I cleaned them out with brake cleaner and a paper towel, put new nozzles in, then tighted the halves to 80 Nm's (with a torque wrench), but there still is a slight fluid leak, even though it's very minimal. No bubbling.

Can I safely tighten them a bit more? Diesel Giant suggests having the injector casing soak submersed in brake parts cleaner.... Might this improve things? I already went meticulously with my fingernails, brake parts cleaner, paper towels, to clean the threading, but maybe having it soak will help.