I think it is how do you know what year it is ? came with 70 b s a parts
Cam plate is pre 67, from memory 67 and 68 have the bracing strap. This doesn’t have it, and it has the notches between the gear positions.
The cam plate also has a worn track so will want replacing, it may start jumping gear if not.
That type cam plate with the right trapdoor should work in any motor. Later stepped cam plates can be bought if it is correct for 70, though if there is free sliding play then you’ll want the later thicker cam plate… or shim the slot.