I think the older the tractor the less problematic... some of today's tractors with tier IV emissions and electronics are very complicated and one sensor malfunction can make the tractor nearly unusable... which is amazing for the way we think if Diesels...
Many members with the early BX series tractors found out the hard way that even a little rain water or washing the tractor could lead to a no start condition... the blinker and lamp switches would short out just from rainwater...
Ultrarunner,
I observed this blinker issue, myself, in 2010, on some (then) late model BX's, on a (used-only) Kubota dealer's lot.
I saw a BX, outside, with a blinking turn signal, mounted on the (left?) rear fender. I tried everything I could to turn it off, but it just kept blinking--s-l-o-w-l-y--like the battery was just about dead. I called him--he seemed to have no clue about the issue....
I assumed perhaps the rain had shorted something, so it's good to have confirmation, but disappointing to learn it's apparently what, in the automotive business, is called a "pattern failure."
I'd say that that known problem lends credence to a concern about the effects of a high-speed salt water "bath," if a gentle rain was enough to short out the blinker on a 2-3 year old tractor.
To paraphrase
The Rolling Stone's "Miss You":
"You know - (tractors) will come and go - They're just like streetcars..."
Personally, as stated previously, I'd skip this salty surprise--but best of luck to kcender, whatever he decides.
My Hoe