E30, cold weather and my dash...

Well, last night it got down to a brisk 25 degrees in my
neighborhood. I was greeted this morning when I got in my car with
another big ass crack in my dashboard. This happened last year as well
during cold weather. I'm not really upset about it today as I already
had a cracked dash and haven't decided whether to replace it or just
cover it yet. My question is this, if I spend the $$$ for a
replacement and the day of my life swapping it out, what do I do to
keep it from happening again? I see a lot of E30's running around and
they all seem to have cracks in the dash. There has got to be
something to put on it that will keep it from doing this. Anyone know
what that magic potion is???