M103 head gasket replacement should like a piece cake to you.
after reomve timing chain uper cover there is a metal pin inside the plastic chain rail
have to remove it first befor remove head
(special tool) if you don't have you can use
a socket and a bolt to force it out (don't damage the plastic rail)when reinstall uper
timing chain cover becareful the cam shaft seal and the u seal.
also chain tensioner must dissembled befor reinstall to do this by push the pressur pin (with detent spring) out of thesioner housing on one direction only....install put the tensioner housing back in cylinser head first then insert the pin(with detent spring)in to housing then the pressur spring and the cap with seal ring back.
hope this help.
MB STARS Master Guild Technician,12 years MB tech
5 years independent shop owner
[This message has been edited by MB STARS (edited 06-24-99).]