CH Yoke assigments

I've been trying to assign the autopilot heading indicator to buttons 3&4 on my CH flight yoke but with no luck. Has anyone been able to do this? A while back when I was first into PIC767 I thought I had success assigning the speed bug to yoke buttons but I can't seem to do that now either. Any help would be appriciated. Oh, and I have looked in the key assigments and tryed the "heading bug indicator increment/decrement" Autopilot commands, but nothing or I should say the the bug moves on the EHSI display but not in the MCP heading indicator and so the plane doesn't move, the two positions disagree.Zan