A note from David Stuart:
The inscription on the west side of Temple XIX platform is somewhat shorter than the text of the south face, consisting of sixty-four glyphs divided into two panels. As on the south face, the text panels flank a throne scene with captioned figures.
The opening date, at A1-B1, is written as "7 Ahaw 8 K'ayab" followed at A2 by the 7-[ku-lu]-TUN-ni. This third glyph specifies the CR as corresponding to the completion of the seventh Tun within an unspecified K'atun, which demands its placement at 188.8.131.52.0 7 Ahaw 8 K'ayab, which, while certainly in historical time, falls well before the reign of K'inich Ahkal Mo' Nab'.
The opening passage rather mysteriously refers to K'an Hoy Chitam I (formerly known as K'an Hok Chitam or Kan Xul), who ruled Palenque from 529 to 565 A.D. (in the Gregorian calendar) -- well before the accession of K'inich Ahkal Mo' Nab' in 721. (For a genealogy of Palenque rulers, click here.)
Rough Prose Translation:
Wuk 'Ajaw Waxak-te' K'anasiy Wuk-ul Tun
On Seven Ajaw, the Eighth of K'anasiy, there are seven stones.
Mi'-eh-aw mi'-winik-ih-iy 'oxlahun-hab'-iy, waxak-...-iy
No days, no winals, thirteen years, and eight k'atuns later
Waklahun-eh-aw wuk-winik-ih-iy cha'-hab'-iy
Sixteen days, seven winals and two years later
Twenty-four days later
Wuklahun-eh-aw wuk-winik-ih-iy cha'-hab'-iy
Seventeen days, six winals and two years later
Three days and two winals later