The method of repairing the broken yoke is described (and with pictures too) at Vendor Amusements' forum:
http://www.vendoramusements.com/bbs/nph-YaBB.pl?num=1145316560
I am repairing the dreaded broken WG 9200 yoke, following directions in the link
provided by Ken Layton. I positioned the yoke pretty accurately, using broken pieces for registration and silicon glue to hold everything in place. Picture is square and the correct size, but I need help cleaning up some convergence and color purity issues. The purity rings are still glued together as a set, but can be moved and rotated on the neck. I have not been successful getting complete convergence at both the top and bottom of the screen. Also, when checking the solid color test screens, RED has some Green in the upper right corner and some BLUE along the right edge. Green has some Blue in the upper left corner. The solid Blue screen also has some Red in the upper left corner of the screen. I have not yet found a position for the ring set that corrects these issues.
This is my first attempt at this type of repair. There is no substitute for knowledge & I'm hoping to find some here! Thanks, Denny