Looking for bore size of L28ET oil jets

Hello,

I own a 280Z and in the book "How to Modify Your Nissan & Datsun OHC Engine" by Frank Honsowetz he describes enlarging the oil-jet from 2.0 mm to 3.17 mm to increase oil flow to the head to improve oil lubrication of the Cam and rocker arms.

I found out that the L28ET uses a different oil pump and different oil jets.
Unfortunaly, I cannot find the bore size of these jets anywhere and I am really curious if the Nissan engineers increased the oil flow to the cylinder head for the Turbo version.

Does anybody have the opportunity to measure the openings of the oil jets for me?
Thank you very much.