2008 4.6L mustang

The easiest way I've found to find parts for any car is to use RockAuto.com (no affiliation). Go to the site, drill down to your vehicle, then find the parts. Not that you need to buy from them, as I still search other sources. However, their parts indicators are usually spot on and give you exactly what you're looking for. Use their part numbers and brands, then do a search for those specific parts to find the best prices, or go down to your local parts store and buy them their. This works well here in the States, though I don't know a good source for parts searches in other parts of the world.