Starting a build thread is the best idea. You can put your thoughts to your build and we can comment. Itll help the direction of the build. Keeping ideas fresh.
Like lwarrior1016 stated, hack an eddy intake up to fit the wider 5.4l. Its what I did. Worked out great. Only thing negative, the stock hood. I had to cut an opening for the plenum. I could run an aftermarket hood with a slight cowl, but funds chose for me not to.
The 5.4l is a great deal heavier and needs to be considered to the direction of the car. For me, a weekend cruiser.
Valve hole size depicts a choke point at a particular piston speed. The phenomenal piston speed of a 5.4l achieves the choke point early! So no mater what cam or intake, throttle body, air intake....a 1.650 hole will only flow so much till its maxed out and chokes the piston capability of pulling in air efficiently.