If you know someone who knows these cars well, and is in the area, take him with you to go talk to the guy and see what else he says
Otherwise, tell him there is no such thing as (those two items), he has no idea what he's talking about, and take it elsewhere.
Read up on how much oil you should put into the 7M over on SM/SF (or here, if the thread is here)...7.5 quarts won't hurt a thing. In addition, the stock gauge isn't exactly accurate.