Timing Cover..."Stupid Question"

I must be missing something...I have played with SB Mopars all my life (20+years) and have never had this problem. I just picked up a nice 69 Dart GT 'vert. 318 all original except for the Holley carb. I went to do the basic tune-up and discovered there are no timing marks cast into the cover. I have looked on both sides and from the bottom and cannot find any timing marks like I am used to seeing. What am I missing, without pulling plugs and valve covers, how can I set initial timing? My timing light lights up the mark on the pass side right around where the timing marks should be, but they are not there. The cover is un-modified right down to the cast iron water pump.

HELP!!!!!!!!!!!!!!

Vic in Phoenix

92 Spirit R/T
91 Spirit R/T (Parting Out)
89 CSX
88 CSX-T TIII?
87 CSX
87 Shelby Lancer
84 Rampage TII
97 Diesel Ram
69 Dart GT 'vert