'69 RS/Z, "Numbers Matching" but is it original?
 

Interesting observation noted by William over at the CRG. Trim tag looks good and it's definitely a rare Z in Butternut Yellow....

Link to 1969 Z/28 auction

Link to Camaros.org post

https://i.ebayimg.com/images/g/YYwAA...bx/s-l1600.jpg

https://i.ebayimg.com/images/g/ENgAA...aA/s-l1600.jpg

https://i.ebayimg.com/images/g/nggAA...Zk/s-l1600.jpg

That engine stamping is not legit also says trans is P9H27B and no pic of stamping, but I would say that's also a stretch for this car compared to other cars built in this time period.
JMO

Great looking car and rare color, but I'd love to see the pre-restoration shots of the car.