I bought a used 04 GMC Envoy SLT (with the thrid seat). The Owner's Manual was not with the vehicle. I have two questions. First, does this model of vehicle have the latch system? If it does they must be way in there because I can't feel that they are there and I do not see them. Secondly, is there a tether anchor for the car seats sitting in the second seat? I have looked and felt everywhere around the back of the seat and I don't see or feel anything. Does anyone else here have that model and make of vehicle? TIA