Heat Riser for 250 ci. Straight Six

[Stock72c10]

The heat riser on the exhaust manifold on my 1972 250ci straight six is shot. The counter balance is hanging and the spring is shot. I have two questions, is it even necessary, I run a manual choke, or can I just wire it to the manifold in the open position? Secondly, what is the open position? I take it it is when the counter balance weight is hanging down? I would rather not take the exhaust manifold off to find out.