GUID of dimensioned items

I use the CURVELENGTH textfield on arc angle dimensions A LOT and as such I am getting bored with having to go through the dimension edit form each time to associate the dimension test to the length of the arc object.
Through scripting I can create the dimension and then reselect the arc so that the dimensionusertext can be used to update the created dimension. This works ok in model space, but not in a layout with a detail viewport.
Is it possible to get the GUID of the picked arc used in the dimension command?
Going forward I would also like to be able to get the GUID of a point entity when used to create a leader. Same problem, but wanting the X,Y & Z co-ordinates displayed on a drawing sheet.

Thanks

Not the full answer, but this might help you.