I’ve seen a bunch of original rotors with that groove in the middle…but I can’t attest that those are for a 70, as Fred said.
The ones in the pics are 1 piece rotors with the cooling groove. IIRC there. was a change over from the 2-piece to 1-piece rotors during the 70 Model year. I don’t remember when that took place. Duane PS, I think they are dated, so you might be able to tell if they are correct for your car.
My car is an 04E car, and it came with the two piece rotors, as far as I know. Every other brake piece was correct, so I suspect the rotors are as well.
Most of the rotors that I have run across 70 are two piece (kind of a hat) and 71 with the groove in the middle. It should also have a date.. I will see if I can get some pictures.
Other than the date code not on my face , same number on drums, never have seen the split rotors before