The big three ....DORKS

x2 on parts lookup before you go in.

I agree Napa is more likely to have people that at least half know what their doing, but even back in the days of knowledgeable parts clerks, us Mopar folks still had a tough time.

I've gotten to where I almost always look up a part and get the number, before I go in. It also usually lets you know if it's in stock at that store, or another one. Sometimes you can pay online, and take in the reciept, then just walk out with the part.