Karl,

We run ours first behind the diamond wires (this is a bit of a compromise) then up through the opening formed by the spreaders, then just underneath the trap wires and shrouds such that the halyard will rest in the corner of the mast hound just under the shackles. When you do this, however, you need to make sure that the main stay shackle can't slide from side to side and pinch the halyard.

On my F18, I put a small stainless eyebolt through the hound nearest the mast and just between the trapeze and the main stay holes. I run the halyard through there and it's worked terrifically. The blue N20 has a special sheave mounted up high (I didn't do this bit) that the halyard runs through to keep it clear of all the rigging....pictures...I know. I'll try to get some.