i own an 07 TL type s and well i'm at 92,000 miles and the dealer is saying that its almost time to change the spark plugs and adjust the valves. I had contacted a mechanic and he recommended to also change the valve cover gaskets and the intake plenum gaskets. If you have done this service on 04-07 TL what else to you suggest to get done or needs to get done. thanks in advance for the help