Here is a great thread on it:
http://67-72chevytrucks.com/vboard/s...d.php?t=559596
and another post about it:
http://67-72chevytrucks.com/vboard/s...5&postcount=54
Here is a good website that explains it all:
https://www.sounddeadenershowdown.co...-vehicle-quiet
You can get it all online. The issue is that MLV is heavy. You can get different pounds per square foot but the shipping is what kills you. If you can find it locally you are golden.
Its kinda hard to work the MLV in tighter spots and depending on what you have close to the floor you might have some clearance issues (gas peddle). Ideally you would want it completely connected. I have used it on other people cars and it makes a huge difference.