what are the best spark plugs for a 2003 gt, its got 49k miles but im gonna change it for 50k what else should i do for this tuneup, i already did the air filter, should i do gas filter?

 

Throw the orginal motorcrafts in. They always seem to work best for me. Definitely do the gas filter and might as well throw a pcv valve on the list too. Depending on the tranny a fluid change(manual) or a fluid and filter change(auto) wouldnt be a bad idea either.