[RonKahn]

Just plan on checking the runout with a dial indicator. Then go from there. There are offset dowel pins available from many manufacturers. I highly suggest, regardless of price two options. Either the Lakewood offset dowels or RobbMC offset dowels. The Lakewood options fit the block very well and are accurate. I drilled a tapped a small set screw in the block to keep the pins in place so whenever I have to pull the bellhousing, they stay in place. The RobMC dowels have a center set screw inside the dowel that are nice, I was going to go that route as well.