Camshaft oil spray bar o-rings missing?

[lts 0]

Rebuilding my XU5Ja. The camshaft had alot of wear, so i was thinking oil supply pipe could be clogged.

 

Cleaning and then refitting it, i notice that all of the unions seems to be missing o-rings. The haynes manual however, say:
 

"Carefully ease the oil supply pipe out from the top of the camshaft bearing caps, and remove it. Note the O-ring seals fitted to each of the pipe unions on later models"

 

 

"On later models." Mine is an earlier model, so that means it should not have o rings at all? Did the design change, or would it make sense to fit them also to my model?

[welshpug 1,691]

if there is a groove there I would presume there should be o rings.