That's too bad. I should've taken pics but it was work, not fun muddin. Our .mil trucks kept getting stuck. Worn out tires didn't help.
I had an LAV25 for the first part of the current war and what they did (aside from being able to float and having 8 wheels) was had bilge pumps and an open top. The water got pumped out faster than it could come in through the small leaks, and only if you swamped the opening in the top, would you sink (I saw that once, nasty recovery). Maybe someone motivated could bucket the motor with plastic panels and cover most of the openings, then just run a pump for when it fills up.