You can easily tell it is a 1976-80 KV75 frame without looking at any numbers. It is not a 1971-75 MT1 frame.
The difference between the two generations were subtle but a main difference was the way the seat mounts to the frame. A MT1 seat bolts to the frame while a KV75 seat has spring-loaded latches.
If you look closely you can see this frame has the two posts for the KV75 seat latches rather than bolt holes so it is a KV75 frame.