He's not a conservative.
In an interview with TAS Williams rejected the label "conservative" and called himself a "radical for individual liberty." What's interesting to me, however, is that both Rand and Williams were popular with conservatives. To this day many people think of them as conservatives. Williams died in December, and he had spent so much time with conservatives that his NY Times obituary called him a "conservative economist" in the headline. I think it's a credit to conservatives that they find value in the ideas of radicals like Rand and Williams. And it's a telling fact that the liberals have rejected them.