Most of the newer engines have an internal oil passage that feeds the head, so the line is not needed. I believe it feeds the rocker arms through a drilled hole beside the center head bolt on the passenger's side. If that gets clogged, there's a provision for an external line to be added by putting a fitting into the 1/8" pipe plug in the head near that bolt. The ones I've seen with the add-on line get the oil from the port on the driver's side where the pressure gauge line attaches. The line diameter could be 1/8" or 3/16".
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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