Advaned Auto parts GENIUSES!!
I used to work at Home Depot in the electrical department. I knew about all the products we had but if it was some random commercial piece we didn't carry or something about electrical codes (which we weren't supposed to talk about anyway) then I had no idea. I don't know how many times guys would come in and ask me how deep they were supposed to bury their conduit in the ground. I'd tell them that they needed to go look at the building codes because it changes for every city and county. They would always respond with "Look, do you have a REAL electrician that works here?". I'd say no, real electricians are out doing real electrical work and making lots of money. They aren't working at Home Depot for $9/hr. That would usually shut them up.
Remember real mechanics are out doing real mechanic work. Parts store employees are normally younger kids working part time and trying to make it through school. Go in educated and knowing what you want because we know more about these cars than 99% of the parts store employees out there.