The professional fishing tournament "Bassmaster" has a article on a pro fishermen Tim Horton and Randy Howell, traveling with a truck and trailer by Zephyr Travel System ( www.zephyrtravel.com)
. Appears to be 25ft truck conversion with a 32 ft stacker trailer. Interesting use of a motor home. The article states they put both tow vehicle and boat on the upper deck of the stacker trailer.
I've not heard of the Zephyr conversions before, their web site indicates the are in the bus conversion business for the Nashville music industry.