I've researched this and I know the consensus is that after engine #M06834, engines have production installed head gaskets. I'm looking at a '91 with engine # M07125. Is it safe to assume the motor definitely has factory head gaskets?

 

Not sure of the exact cut off point. Is there a specific concern with that engine? I just rebuild my 1990 engine that went 245K miles without head gaskets. I would focus on the overall condition of the car and the maintenance that's been done.