Michael,

I fully agree with Nick.

Before you fit your position the indicators, have a sail around and take a marker with you so you can mark the position of the sail on at an adjacent point on the mast when the downhaul is fully released. This will probably be different from what you see when you first hoist the sail on the beach.

Also measure how much overall downhaul can be achieved and mark that too. Use the top mark as your locator for the strips.

Regards,

Peter