'70 Chevelle SS396, GM Canada Trim Tag....
 

Looks to have an original Oshawa trim tag identifying Z25...but I can barely read it. Wonder if this is the aftermath of a sandblasting effort? In any case, lots of patchwork evident in the trunk and the body panel fit doesn't look to be the greatest.

Link to 1970 Chevelle SS396 auction

https://i.ebayimg.com/images/g/x1MAA...bA/s-l1600.jpg

https://i.ebayimg.com/images/g/mfoAA...YH/s-l1600.jpg