Why not just get a new dash form Cheyenne Parts or USA1 Industries. I realize they are more money, but it sure would save you all the aggravation of the work involved. I have seen more Coverlay installs that look like crap vs. one that actually turned out good.
http://67-72chevytrucks.com/vboard/s...d.php?t=736613
https://www.usa1industries.com/1979-...nyl-style.html