Just wanted someinfo on what gap I should set my Motorcraft Plugs, if Im running 98 4.6 coil packs on a 2002 5.4 motor..

1998 F150 4.6 to 5.4 Swap

 

.052 to .056 all three engines that covers both type ignitions.
An .052 gap should stay longer accounting for errosion but very sleightly make the idle a little rougher but you may never feel it unless you were to make a compairison.
Good luck.