Kirk- answer depends on configuration of the TB in question.
I've just done an '05 Ford V6 4L TB, it was plastic and required a different strategy than aluminum. Plastic Ford TB's are thinner bore walls, I advise a Med. bit for those, and substantial epoxy back-filling is needed in several places, I also did a complete fill-in, bore wall contour match and IAC air hole drilled thru the fill for the IAC air port.
Next, if the TB in question is aluminum, is it cable drive or Drive By Wire (DBW)? I've not yet done a Ford DBW- but on the Chevy Vortec ones that are DBW there's a specific strategy for Groove location, and I suspect Ford's will be similar. You are looking on DBW TB's for a dark carbon stain that builds up behind the throttle plate on the bore wall, this black stain will go right up to where the throttle butterfly plate is positioned at hot engine idle RPM. DBW TB's typically lack any IAC passage and valve, instead the computer positions throttle plate at a slightly open angle at hot idle. The plate is moved further open for cold start idle, and will gradually close to the hot idle position as engine warms up. So- the plate will spend most of the time at the hot idle position when AT idle, therefore fine dirt and residual fuel vapor in manifold at hot engine shutdown will build up a black stain on the bore wall. The stain will have a sharp or pretty sharp edge to it at upstream end, denoting where the plate sits at hot idle. The Groove must be positioned a bit downstream from the edge of this black stain so the plate does not engage the Groove at idle. If it does, you can have an engine that will be making more power than normal at idle and not idle right. MY first Chevy Vortec 5.3 DBW Groove-the truck idled at 18MPH, had to stand on the brakes to hold it, would not idle properly. Had to fill the Groove and re-do it.
I did a Ebay quick search for '04 Ford 5.4L Triton TB's- and saw varying results of TB types. Some cable drive single barrel ones, some cable drive 2 barrel ones, and some single barrel DBW ones, and descriptions of these Ford 5.4 TB's covered the whole range of model years. I have done Ford Triton 6.8 and 5.4 Triton's, but only '99 and '03.
With the Ford DBW type's, there is NO IAC, idle air goes past throttle butterfly plate, depending on throttle angle. Further, (I don't know EXACT details yet) the Ford DBW TB's require some special procedure if the TB is swapped. SO- if you are going to do a Ford DBW TB Groove--it's best to do the one that's ALREADY ON the vehicle to avoid the swap issue, far as I know so far. AND-- you definitely DON'T want the throttle body to have been cleaned inside, you need that dark stain to indicate hot idle butterfly position. W/ the Chevy Vortec's we just put a business card under the plate on opposite side of plate from Groove, and hold or block the plate closed against the card, this uaually works to give the right position to cut the Groove. I'm thinking that Ford's will be similar. Basically- you look at the stain, and put the plate a bit downstream from that edge, so that the plate will cross over it at light acceleration. You have to find a position so the Groove is engaged at the right time, not instantly right off hot idle, but just a tad after that in plate rotation.
Kirk, to give more accurate info to you, I NEED to see pic's of what you're gonna Groove. The 99-03 Ford's I've done, 1 and 2 BBL types, were cable drive, aluminum, very straight forward, easy to get great results with. Newer ones may require more attention and care, I need to learn the newer ones too. I was going to wait for results on the plastic '05 4L V6 Ford I just did to post it w/ pics. But if you are looking at a plastic Ford TB, lemme know here and I'll post the pics and explanations of strategy I used.
If any other Gadgetman have done the '04 and up Ford 5.4L Triton, or, heck, ANY Ford's newer than '03, please jump in here and share!
Happy Grooving!
Tracy G