i have a 2003 f150 what size of wrench do i need to remove line on egr valve or what steps do i need to take

 

....7/8" open-end for my '97....plenty of Liquid Wrench as well.
Spray the fittings wet with LW, wait a few minutes for the stuff to penetrate the threads and then tap the fittings and the tube adjacent to the fittings with a small hammer, then get the wrench on the nuts and pray.