recently just did head gaskets on my lly, ending up braking 2 return line fittings that go into the top of the injectors. my buddy found me a return line repair kit from XDP for $20, figured I'd give it a shot. well, now the driver side return line fitting, 3 out of 4 fittings are leaking. has anyone had any problems with these repair kits before? should I just replace the whole return line with GM one?