My all original unmolested car may not be so original...
As MOPAROFFICIAL mentioned there should be your year code, displacement and fuel type stamped right behind where your coil mounts to the block.
Then you can see if it's numbers matching to your vehicle by checking the vin stamp on the block located towards the rear of the block, seen from the passenger side of the car.
If yours is the original 70 engine, it should be stamped "F 225 R "