You have to carefully install each injector into the rail with oil on each o-ring, or the ring will stretch, pinch, twist up and bind, etc. Dont put the o-ring in the fuel rail injector bore first and then force the injector in. The O-ring must be on the injector before it goes into the rail. Then once the injector/rail assembly is together, you carefully press each injector into the injector bungs, but you dont fully seat 1 injector and then move on to the next. You push it a little bit into the bung, an then the next and then the next. You keep doing this gradually till every injector is fully seated. Otherwise you'll be cocking each injector so much that something could get damaged. You have to have oil on the lower o-rings, and the injector bores should be totally clean and free of grease and debris, and then you rub a tiny bit of oil into each bore, and on the little countersink, or lead in if you want to call it that. Then you install it. Never put them in dry. Your only option right now is to pull the fuel rail back out and inspect every o-ring. You most likely tore one or more rings. Pull the o-rings off, and stretch them slightly to expose any cuts there may be on them that you normally wouldnt be able to see by just staring at them. Slightly stretch...these arent rubber bands. The key to doing this right is cleanliness and extreme patience. If an injector doesnt seem to want to go in, dont ever ever ever force it. If it takes you a day to get the injectors, so be it. relax and have fun.