[Longhorn Man]

they've been spraying that crap here for over a week... and it's only dipped below freezing (with no rain or snow) a couple nights.
The thing to remember, is back in the rock salt days, once the salt was dried up, it was no longer causing damage.
Now... if it's on your vehicle, (on exposed metal) it'll suck the humidity out of the air clear down to 30% humidity. This means that what ever you don't get off of there, can be causing corrsion issues even after all the snow is gone, like in may or july.
The other bad thing, the molecules are much smaller, and can literally fit under the head of a rivit.
Another bad thing about this stuff, it is an airborne issue too. Go outside on a winter day, (within a couple miles of a freeway) lick your lips, then lick them again in 10 min... you'll taste the salt. So even if it is parked, and under a tarp... it'll STILL get the brine all up underneath it.
The very best thing you can do, you already said you can't do... park it.
To thwart off the problems on a driver, you need to try and have paint on everything underneath. Even if you just get under there with a can of black spray paint (not flat, has to be semi gloss at a minimum) and cover everything that isn't painted... exhaust, frame, tie rods and ends... inner body panels like between the inner and outter bed panels... this will go a long way to help.
Mostly, wash your truck every chance you can. if it is above freezing and you have the chance, go to the coin op car wash and blast it off, Mostly worry about the undercarrige, that's where it does most of the damage. under the hood too, the lower cab firewall and innerfenders, under the battery tray... all of it.
Then come spring time, spend an hr or two under your truck with some good spray degreaser/cleaner (I like Spray nine myself... Simple green works OK too) and plan on getting wet.