I would use original equipment ACDelco Iridium spark plugs part number 41-103 for best results.
ngk or autolite platinum series
autolite double platinum you can find them at most auto part stores
Don't do it. Bosch Platinum +4 plugs are not designed for your Ranger. Use the correct Autolite plugs. I believe they are called "dual platinum" or something like that.
The Packaging. Autolite MAKES Motorcraft
All iridium plugs never need gapping because they are 10 times harder than a platinum plug.
How to change the spark plugs
Ford sold Autolite to Honeywell when they began manufacuring the Motocraft brand.
One can purchase an Autolite spark plug from a local store that carries Autolite products. One can use the store locator on the official Autolite website to find a location near him or her.
AC Delco Iridium spark plugs.
ac delco spark plugs are type that originally came with 2003 GMC envoy
.034
Autolite spark plugs are avaible at most parts store across the country. They are vrey common.