I hooked mine up parked it with my cans loose and had a friend move them in boat while I was at rope length until they sounded best. Honestly I couldn't tell much of a difference so left them straight. My horns are inside for one simpler reason though......
In a dd I didn't want the horns right in the walkways so I put them over the doghouse. If you've never stood up in front of these things blasting you'll understand later.