Mine's in the lazarette next to the grease pump (top Port side). Connect a rubber radiator hose from the cylinder head outlet and run it under the length of the cockpit to the lazarette and then up to the anti-siphon tube which is held in place with a piece of string ~100 mm below the deck. (and about 450mm above the waterline) The anti-siphon tube has a small pipe on top (internal dia ~3mm) which his attached to a plastic pipe that leads through the lazarette cover upstand to discharge onto the deck and allow air entry when the engine is stopped. (Warm water trickles out at 3000+ rpm). The return pipe (again rubber radiator hose) is led back along and tied to the flow pipe and is clipped onto the exhaust knuckle. The total length of rubber pipe you will need is about 14-16 feet.

My anti-siphon tube is made of copper pipe the same diameter as the cylinder head outlet and the exhaust knuckle inlet. Use the appropriate size s/s jubilee clips and plenty of cable ties to make it all neat and tidy. The anti-siphon the came with the boat and I've no idea of its make.

It's straightforward to install and works very well.