I prefer to use a rear paddock stand only on my 998 but I can fasten the bike securely on the stand very easily.
Just give yourself plenty of time to load up and make sure the bikes are secure. I tend to use the frame of the bike to fasten it down both front and rear, plenty of cloths etc to avoid any rub damage
You need to be sure that the bikes are secure if you have to brake hard or heaven forbid run into something, they are unlikely to break free under acceleration in a Transit unless it's one the specials with an F1 or cosworth engine
Enjoy yer day.
Ray.