Oh, I see what's confusing this all up...
First, a bit of history about it: in 1974 when the K5 was first appearing, it got some of the leftover K4 fuel tanks with the 1-outlet, downward-pointing spigot on the left side near where the choke lever is located. The carb rack was still the K4 type with the 2 fuel hose ports (one between carbs 1-2 and another at 3-4 side). Honda 'resolved' this by installing a custom-made tee in the fuel line after the hose passed over the top of the 1-2 side's carb mount hole (ignoring it completely) and almost directly above the 1-2 carb's fuel tee. This made a very short (1.5" or so) fuel hose drop into the 1-2 side, then the hose bent around the back of the #2 carb to run to the opposite side. It was important, in that rig, that the hose to the 3-4 carbs not be too long, or it would create quite a fuel bubble at the highest point, which increased the time needed to fill the 3-4 carbs.
All this worked OK when the speed limits were 55 MPH.
That all changed when the speed limits went back to normal.
When we had to make fuel 'go faster' to the carbs again, this setup wasn't working very well. While the 1-line feed can drop fuel fast enough, the horizontal line to the 3-4 carbs, with its constant air bubble, about the middle of the run, fought the delivery to the far side. The first 'fix' was to get the K4 petcock with 2 outlets, but this puts the rear hose directly over the left-side choke lever (which became the right-side choke lever on some of the 086a carb sets, which aren't all that common). Today those exotic parts are hard to find...
So...Carpy forced me to solve this when one of his customers came to my house with his almost-finished cafe' bike with Carpy tank, which used only the 1-outlet petcock like yours, pointing downward, in almost exactly the same spot yours has. What I did fixed the problem well, but is a little complex and I don't have pix (it was well before my book came out), so I'll attempt to describe it:
1. I came out of the petcock with the 5.5mm Honda hose, over the top of the carb mounting bracket by the 1-2 carbs, then to the space between carbs 2 and 3, back by their airbox inlets.
2. I installed the tee back there, lying flat, by entering one side of it (not the middle of the tee).
3. I ran the opposite side of the tee to the 3-4 carbs.
4. I ran the 'top' of the tee to the 1-2 carbs.
5. I rotated the tee to lie flat down, with the petcock's line running over the top of the 1-2 carb's line so the fuel was always flowing downhill.
In the end, the tee rested sort of mid-air above 2-3 air inlet hoses from the airbox and the 2 hoses to the carb feeds rested atop the air inlet hoses enroute to the carb fuel tees.
I'm sorry I don't have any pictures to show of it. But it resolved the problem and the bike could run to 100 MPH without starvation troubles (which is mighty handy to have on I-25 north out of Denver where it is mostly 90 MPH traffic, and the owner lived in Firestone, north of Denver, back then.)
Another Crapy nightmare forced me into another solution about 1 year before I did the book. This one had a Carpy tank with the petcock outlet coming out directly over the choke lever on the left side, no room to operate the choke if you added a fuel line to the horizontal outlet spigot, and no petcock alternatives (if you're getting the idea that I dislike Crapy parts, you're getting warm...). I made a 1" piece of fuel hose from the petcock, into which I installed some 1/4" copper pipe so I could bend the pipe up and over the choke lever (when it was lifted), then bent another 90 degrees into it to get it behind the carbs from the left side. Then it went to rubber line for 1" to the tee to feed the 1-2 carbs, then hosed over to the 3-4 side. I then had to offset the choke linkage to close the 2-3-4 carbs long before the #1 carb choke plate was closed, and the rider had to cold-start using just cylinder 2-3-4 because it wasn't possible to close the #1 choke plate all the way. (I used to keep notes about these Crapy parts...). Then, about a year later, this bike came back: the entire lining of the [fiberglass] tank had shed itself into the tank, clogged every orifice in the carbs and fuel lines. After 2 more years, the owner's battle with Crapy netted him a steel tank (unlined, so he POR15-d it FIRST this time...) after I CUT OFF the petcock spigot Crapy had added DIRECTLY over the choke lever, welded the tank shut again, went to the other side to mount a spigot for a petcock with 2 outlets, and mounted the whole tank 3/4" higher (by cutting off and relocating the front tank mounts downward so the coils still had a place to fit under this tank), then made nice, smooth 5.5mm hose transits to the carbs. The bike's been fine since then.
Don't buy Crapy tanks for these bikes, IMHO.