Currently inwork replacing injectors and all is well until went to remove the one-piece injector fuel return line. This line is held on by a 5mm bolt head at each injector and 1 "banjo" fitting at the upper right corner (passenger side). While trying to loosen each 5mm bolt on this line they keep trying to strip out. Is there a trick or some retaining clip I'm not seeing? Shouldn't these bolt heads simply loosen. This one-piece line has to come off before the individual injectors can be removed. Any ideas please.