I may have found a NOS dash for my '70 I am restoring.  I have done a little research about preventing cracks and I am curious if anyone has any updated information they care to add.  This is what I plan to do:
Store the car in a temperature controlled room that has very little temperature fluctuation.  The garage has heat and and AC.
Cover the dash and/or windshield when you are parked in the sun. 
Treat it with Vaseline?
Don't use Armor All or similar products.

Does anyone have any other advice?

 

Anyone?

If anyone has a dash that is not cracked, can you share your secret?

Never drive during the day I have one of those felt/carpet dash toupee with reflective foil sewn in, I leave it on the dash all the time except for cars shows. MSA sells them and you can get them on ebay.

I have 2 hairline cracks on the top of my dash and I think they've developed after I bought it (3 years ago). According to the p.o., the car was always garage kept and I have kept it in a temp controlled garage. However, during take down and restoration, the workshops were not temp controlled and I think that's what produced these 2 tiny cracks.

I used this on my console's hairline cracks, worked great.  I think it was about $4 at Lowes?