I just installed my VA compressor the other day....I have the stock style alternator mounts and they work perfect.....Also, the compressor brackets are the same for either manifolds or headers....they give you several extra spacers for the compressor brackets to work with either...so having headers should not change anything!
Here is a good thread of the VA install....he also relocated the alternator....
http://67-72chevytrucks.com/vboard/s...d.php?t=249479
Here's a couple quick pics of my set up: