Turnbuckles

[psness]

I think my stays are a bit loose, but can barely adjust the turnbuckles as they seem to be the original and "frozen" tight.

(1) How tight should the stays be? Mine are loose enough that I can move the ends of the spreaders back and forth a few inches with them.

(2) Any suggestions on how to loosen the turnbuckles? I already tried WD-40 with no luck.