The old FJ40's are great in almost any terrain and absolutely robust in construction.
I can't tell the year of the Landcruiser, but it appears to have a continuous back window, making it a 1975 or earlier. I had a 78 FJ40, which I owned 1978-1991. They all had little vent doors at the floor level to provide ventilation of the heat emitted from the engine compartment. One time in the summer while living in Wyoming I crossed a stream and forgot to close the vent doors. Obviously my feet got soaked. However, once started into the stream I had to keep the momentum going and wait to drain the floor area after reaching the opposite bank.
Just reminiscing a fond memory. Sorry back to the regular programming.
All owners back then had to engage the front hub when shifting into 4WD, but additionally it was important to close the vent doors when fording water.