Cracked head or blown head gasket????

[mblack18]

Ihave a 95 Altima w/ka engine and I have either blown a head gasket, cracked the head, or both, (my wife, not me). I'm in the process of tearing the engine down to get the head off, and now I'm at the point of finding tdc, and I can't get a clear picture of how to find TDC. I can turn the crankshaft easily, but I can't seem to find the timing markings I'm supposed to be looking for, according to the repair manual. Also if you could give me some pointers on this procedure,blown head gasket or cracked head, I would really appreciate it. Thanks,