I posted my A7V postcards and other tanks or military issues on my website. One A7V still needs to be identified! Check this link and the Tanks link on the site for other interesting postcards from my collections of Tanks, armored vehicles and trains, and horse back riding soldiers!
Eric, the one you require help with is 543 as well, taken at same location as the frontal picture of 543 "Adalbert", Abteilung 3, approx. mid-June 1918.
Good sight! #58 shows on the front right side of the tank, next to the track (left side of pix for you). Did not know it was the chassis #. What about the 8?
The last digit of the chassis number is missing. The choice is a number is between 580 and 589. Eight vehicles formed one Armee-Kraftwagen-Kolonne (Raupe), so this would be vehicle number eight of that AKK(R).