If you have them, maybe loader forks would work. Mount a couple lightweight tubes to the underside of your tank and then, with the sprayer boom facing forward of the tank, slide into the tubes with the forks.
I personally wouldn't worry too much about driving over the sprayed area but the mist might be another thing. Maybe a inexpensive mask or respirator would protect enough for the few times a year you use it.
The more I read, the more I am impressed with the utility of forks. People use them for so many more things than lifting a pallet. I'm trying to design a grapple setup that could be interchangable with my forks or bucket.
Anyway, my 2 cents.