For the miniatures that were primed or painted, a trip to the tub of Pine-Sol to loosen their paint. For the others, I ground off their faction's insignia with a dremel and then sprayed them gray. Then I block painted them using a fairly simple palette so that even though they are sculpted differently they would still "hang together" visually.
Then I dipped them in wood varnish, dabbed off the heavy pools, and then left them overnight. The next morning I sprayed them with matte varnish and then added the flock to their bases. Here's the first four.
From right to left: Jupiter, Sarge, Billy, and "Boom Boom" McAllister.