That leaves the fuel pipe from the in line filter to the engine to blow through/ream out and just possibly I suppose change the in-line filter again. After that it will be a case of injector pump out and into a local 'mantling shop' Before that though some intensive study of the workshop manual. There is a recommended diesel mechanic lurking around the place and I might just get a quote for removing/testing injectors and injector pump. It might be money well spent and would/could cut down the time spent in the marina which in itself would be a saving, albeit a small one.