I think its in the FA-18.dll which the lines can be found in the panel.cfg, see below:
[Vcockpit01]
Background_color=0,0,0
size_mm=1024,1024
visible=1
pixel_size=1024,1024
texture=$F18_A_GAUGE1
;1 = left DDI
;2 = right DDI
;3 = center DDI
gauge00=fa-18!MFD, 450,4,440,440, 1
gauge01=fa-18!MFD, 4, 452, 440, 440, 2
gauge02=fa-18!MFD, 4,4,440,440, 3
gauge03=FA18_HUD_VC_R!FA18_HUD_VC_R, 568, 465, 461, 508
gauge04=fa-18!UFC_WINDOW, 4, 898, 193, 58, 1
gauge05=fa-18!UFC_WINDOW, 204, 898, 193, 58, 2
gauge06=fa-18!UFC_WINDOW, 4, 960, 193, 58, 3
gauge07=fa-18!UFC_WINDOW, 204, 960, 193, 58, 4
gauge08=fa-18!UFC_WINDOW, 450, 446, 193, 58, 5
gauge09=fa-18!UFC_SCRATCHPAD, 648, 448, 264, 57
gauge10=fa-18!UFC_COM, 400, 899, 47, 58, 1
gauge11=fa-18!UFC_COM, 400, 961, 47, 58, 2
These lines:
gauge00=fa-18!MFD, 450,4,440,440, 1
gauge01=fa-18!MFD, 4, 452, 440, 440, 2
gauge02=fa-18!MFD, 4,4,440,440, 3