I believe you will need to remove the heater box with core in order to remove the valve. It has the temp sensor attached to it with the copper wire that goes inside the box and onto the back side of the core. I had mine rebuilt by Old Air and didn’t get into it so I don’t know if that connection is something that can be disconnected inside the valve, would be nice if it is.
I guess if you don’t care about the “automatic” temperature holding feature of the valve you could cut the sensor wire and leave it in place while just removing the valve which I believe will function in a fully manual mode without the sensor wire.
Someone here must know more.