Originally Posted by ROLLGUY

If there is no heater installed, it is nearly impossible to get the screw plug out to install one. I believe it is a 17 or 19mm hex. Removing the intake and exhaust manifolds, as well as a 3/4" drive breaker bar with cheater is the only way to get the plug loose. I am sure others have tried it without removing the manifolds, but I can't see how it can be accomplished that way. You may luck out, as some have the heater installed, but no cord........Rich