I see good prices for 5.4s in Econoline vans, some out of a 2003 Expeditions. Isn't the 2valve kept in some later model fords?

Whats the newest I can go and what do I look for to confirm it'll work? 8th digit being L?

I want a straight swap. My current trans is strong and has been maintained properly it's entire life (I have the documentation)

I've been thinking of freshening up my current 5.4, but from what I read on here it's a nightmare to open up and less difficult to just swap the power plant. I got an exhaust manifold leak with a couple broken studs, small oil leak at the rear of the passenger head (read that doing heads on these are not fun)

I'm not looking for how-tos, I found those threads already. I'm looking for straight swap options - or whatever can be done with no customization. (unless it's a very straight forward one!)

I'm fairly decent with a wrench, do all my own work with the exception of welding.

thnx in advance.