While at the ACGG show in Jan 2010, many asked about the purpose of the square upper shank.  You'll find this Wiebe design far easier to install than others you may have used.  There are presently two versions, the Oberndorf and the Burgess.  

Here's the way we do it!

	Cut off the old bolt handle about 3/8" away from the body.
	You'll need some sort of a device to hold the parts in proper position.
	Fit  the parts closely, especially the "root".  This first weld is very important to a clean, neat appearing conversion. Good idea to preheat the joint prior to TIG welding.
	With the old handle out of the way, now's a good time to clean up/ open the bolt face.
	The square shank makes shaping a "piece of cake"--eliminates all the welding build up for proper shape.
	This jig holds the action at proper angle to cut the notch.  I use a 3/8" cabide end mill with the corners knocked off to form a neat fillet   I keep deepening until a 98 sleeve/safety will BARELY engage.   This will minimize bolt "jump" on firing...Now I have a nice additional safety lug.
	Of course, welding has probably softened the cocking notch, needs to be re-hardened.