I have a 1995 F-150 and I just got this crazy idea to swap out the engine and tranny with the new generation engine and tranny (5.4L). Has anyone ever researched this or done it?

 

Yes

It's been discussed many times and it has been deemed a bad idea

 

If you swap the engine, computer, wiring harness, and transmission together as a set, it's not that big of a deal. While I've not done this particular swap I've mixed and matched parts before and long as you figure out ahead of time your "will get stuck" points any engine swap is not to bad.

Swaps I've done, or seriously participted in doing...
Shoved an EFI 460 into an explorer.
Shoved GM EFI (and turbos) onto a Dodge 451 stroker in a dodge truck.
Shoved a Northstar V8 into a taurus
Shoved a 302 into aother taurus (which my buddy converted to RWD first)
Shoved the Triton V10/6sp into an old LTD II sedan.

If you can physically fit the powertrain you want into the vehicle you have, it's just wiring and welding (motor mounts, tranny mounts, cutting the floor for the shifter if necessary, etc) and figuring out the driveshaft u-joints, possibly having to make a new "end" for the driveshaft so it fits old and new parts.

 

I'm gonna do that swap one day to my truck but I gotta fall on a good deal on a donor truck first. My Expy gets the same MPG as my '91 300 but it will suck the headlights out of the F150 and it's dragging at least an extra 1500 lbs. around. I would love to see what the Triton could do without the extra EL BEES.