I'll get on a soapbox for a minute.
Always bring your old bulbs in, and parts for that matter, you have to get them out anyways. A lot of Saab's (just for an example) have two different bulbs listed and it's a fucking PITA when they don't have the old one. One is a 7443 and the other is some bastard bulb for the tail lights. Ford has a lot of mid-year changes along with GM, which makes shit complex as well, along with multiple amperage alternators due to power options, etc. Toyota and Honda are fairly good about this whole keep it uniform thing, but it's always good practice to bring in the old part if at all possible to the store. May make things a bit of a hassle, but saves even more of a hassle overall.