Brent-
I had much difficulty getting them out and I finally ground 2 flats on them so I could turn it with an adjustable wrench and used heat as mentioned above. Once you can turn it, you can work them out. When you go to replace them, I reccomend the Robb MC ones if offset is needed or McMaster for dowels that have a thread in them so removal is much easier.
http://www.robbmcperformance.com/products/dowels.html
http://www.mcmaster.com/ see pull out dowel pins