You would be better off with an aluminum 4V cause the 5.4 is gonna add a whole bunch of weight up front.

Eaither that or a fresh 2v with some Trick Flow heads!
Absolutely Right!!! I was going to go this route (5.4 Lightning w/ Nav heads) But it would require a lot of modification. which IMO don't make much sense.
1 you'd have to go with a K member, and adjuster plate (lowers the engine up to 1") which will clear a cowl hood, NO HOLE)
2 You would have to go with shorty style, or Mid length headers, which IMO bottle necks some of your power to be had.
3 You will need to use adapter plates because the intake would not match up properly, and even still won't after adapter were installed. Flow will be a bit off..
4 You would want to consider going with a custom sheet metal upper because why have all that HP/ TQ but not get to it because your restricting flow from the get go.
5 Simply not worth the amount of work and money put into it doing it RIGHT. for the money, the true bang for your buck, take your 4.6 stroke it , cam it blow it and you will beat the ***** out of any 5,4 anything!
My car will produce 690 to 700+ RWHP safely tuned. My car is manageable and drivable. Believe it or not, a lot better on gas than that 5.4 will ever be.
If your going all out race, then maybe 5.4 fits your needs, but at that point who the hell cars about a custom hood, build it as bad as you can, and spray it until it wheel stands in 3rd gear..
Thats my 2 cents.... keep the numbers matching build what you got. if you have any questions on how to get to 700 hp let me know i have a list of parts. Don't go over spending, there is a lot of that. I didn't buy anything that i didn't need, IE ported 4v heads steeda this steeda that. blah blah..
Jon Connecticut. Good Luck