Heater hoses ribbed or printed on 1969 02A Los build Z

[CAZ28]

I searched but could not find an aprox. cut off date for when the ribbed hoses became the standard. I know the GM logo hoses were on the early cars but when did they phase out? I have to replace my non original hoses anyway so I might as well get the right ones. Thanks for the help.

[william]

I'm not convinced the GM logo hoses were universally used on early production cars. The January '69 Hot Rod test Z/28, also seen in the April '69 PHR, does not have them. It was a very early car. Neither does the yellow JL-8 Z/28 seen in Car Life and Road Test August '69.

The only photo I know of that shows them is on page 120 of JM's 1969 Camaro book. Car was built November 1968.