I realize this may not be exactly what you're looking for, but in August 1971, I bought a used, silver 1970 Judge and it did NOT have a hood tack, so I bought a brand new one from the local dealer in Northern Illinois. I asked the same mounting locations you ask and they told me, "mount it where you want."
So I sat in the driver's seat while a buddy fussed with the location until I could read it easily. A few months later, I sat in a Judge with a factory mounting location--I liked my location better.
Back then, the needles were very hard to see, especially at night, so I disassembled the hood tach and brush-painted it flourescent orange with Testor's model paint, which made a huge difference.
Hope this helps--a little.