It's probably an SS car, but I wouldn't bet the farm it's a 396. CTW was also used for Camaros and other 70 BB applications. I can't read the tag on the trans very well, but it kinda looks like 06A. Seems a little late for the build date of the car if I read that right. The disc brake set up is way wrong for original, as are some of the pieces on the motor. The build sheet tells you it has the SS package, but there's no motor call out in 70. It could have been a 350. No rear swaybar. The SS package didn't include the SS rims.
Now...it's a cool fairly rare color, and if your not concerned over absolute originallity, and it goes cheap, it's ok. I tend to not believe the docs are absolute. Show me a window sticker, a dealer invoice, or pop.
You asked, that's my 2 cents.
