I have a 90 hp Yamaha engine mounted on a 20' pontoon boat with an extended aluminum engine mount platform. Can I attach the TurboSwing to the extended engine mount platform and should I use the XL or XXL size? I also have a aluminum step platform and ladder on the starboard rear side next to the engine. Will the TurboSwing have clearance with the platform & Ladder in the raised position?

For a 90 HP Yamaha you would need the XXL, We have had success in the past when installing the TurboSwing to an extended engine platform as you would mount it to the extended platform. We have had success with installing TurboSwing with swim ladders, you can give us a call or send us an email for more information on the dimensions to confirm this would work on your specific set up.