Harmonic damper installation

I got the company to send me the tech drawing which doesn’t show the inner diameter, but does show the step down in ID in the middle. So I guess it’s supposed to be there.

I’m thinking maybe I try putting it in the oven to open it up and hope for the best.

Also I don’t have a installation tool, but Larry Shepherds book just says to use the crank bolt to install the damper