When I said a factory option, I was referring to the drilled oil gallery plugs. Chevy still has them on the shelf at my local dealer for $5 a set. Im not sure if the gear drives were ever factory, but they certainly had blocks w/drilled gallery plugs. I spoke with several people locally yesterday and one of the guys had a late 90's block that had these plugs. Although I respect your opinion, I still prefer the gear drive over the chain though.