The Boomkicker works by flexing upward and when straight, it is at the top of its travel. Install the Boomkicker with the screw head side of rod clamps facing up to flex upward away from the vang. With the boom height set, position the Boomkicker with fittings alongside the vang triangle to see how it fits. Position is not critical so long as it does not interfere with the vang. It's recommended that both the vang and the Boomkicker make an angle of between 30o and 45o with the boom. Mark the location for the mast fitting.