Piston Pin Bushings?

Hello again folks,

The engine rebuild continues, and now the pistons are off, I've noticed an interesting fact about the pin bushings...

The piston rod small ends have two small holes in them, probably for lubrication. The bushings also have holes that match up to the ones in the connecting rod.

My replacement bushings (which are Kobelshmidt or however you spell it - O.E.M) do not have these holes!

Question: Are these holes necessary or was the design changed?

Follow Up: If they are necessary, I'll have to drill them - any problems likely with this - it should be easy since the bearings are very soft - some kind of lead-alloy most probably...

Thanks,

- roGER (1973 911T CIS).