Further observation....
I just had a scout around to see how these models compare and the first important issue that struck me was the advertised payload difference.
Whilst the Bailey has 500+ kgs the Autotrail only has 285kgs, so you'd have to be very sure of your weights to keep legal. Don't forget that any accessories added to the original vehicle will have eaten into this as well - awning, any extra battery etc etc.
The figures above are only taken from search results so you would need to check them yourself.
Just another 2p worth
Best of luck and let us know how you get on.