I just bought a 1985 Hunter 23, I am new to sailing and am still learning terminology. So here goes, my double back stay simply has a one piece with two rollers on it that connects the two back stay lines. I know it is important to be able to control the back-stay tension but this simple connector is not set up to pull down increasing tension (high winds) or decrease tension (low winds). Can someone coach me on what to buy to rig my back-stay? Thanks!