If it is a McMillan, it doesn't require pillar-bedding.
You'll just be wasting your money.
Quoted from Kelly McMillan himself:
"I'm often asked by customers who would like to bed their own stock but lack the confidence to try "pillar" bedding, "Do you need pillars?"
Because of the construction techniques and materials we use in making our stocks it is not necessary to use pillars. With the exception of benchrest stocks which are almost always glued in and use a lighter fill in the action area than all other stocks, pillars are unnecessary.
Test have proven that the materials we use to fill the action area of of stocks have less than 1% compression at 100lb psi. What that means is that there is not way you are going to be able to torque your guards screws tight enough to compress the material under the action. Why do we put them in every bedding job we do when installing our stocks? Because it's state of the art. It's what has become the excepted way to do things. It's not a fad. It is a valuable technique that is necessary when bedding stocks that use a different method of construction (which almost all other synthetic manufacturers do). It's just that with ours it is not really necessary."
Source:
http://yarchive.net/gun/rifle/pillar_bedding.html
He gives quite a detailed account of why pillar bedding is used, and why they don't require it with their stocks.