Ok I did not know that...just did a quick and dirty dual coil setup...coils are a little sloppy, cause the damn centerpost kept spinning on me, but now that I know that's by design.
Yup you should be able to tighten via the center post as if it was an adjustable c.p. atty. I'm digging those hex set screws. I might need to do the same as i'm getting tired of screwing up my resistance with long as coil legs leading up to the top of the block. Are your center block post holes "deeper" than your negative post holes like mine? i.e. do you screw in your positive block screws more than your negatives? That's my prob... but set screws would eliminate the depth guess and allow me to tighten to the bottom.