o rings are not to bad to do. just did them on my truck. might as well test the glowplugs while you are in there or just replace all of them if you dont mind the cost also inspect your valve cover gaskets and harnesses for burnt pins.
Thanks to everyone for your help, I was not sure if there was another way for oil to get into the fuel system. I have pulled the injectors and flushing out the fuel galleys and reassembling.I will update all with the out come. Thanks again for the help..