Calling out block name with leader in paperspace

I think something like this was discussed a long time ago, but I can't seem to find the right search terms to find it.

My goal is to put the name of a selected block (which is located in modelspace) into the text of a leader.  I never found a viable program that would do this automatically. The routines would either put the arrow of the leader at the block's insertion point, or would not work at all if the block were in model space and the leader in paperspace.

At some point I was instructed how to create a leader that had a field containing the block name by using a special code in the text.  Then I could make copies of the leader and text, and when I attached the new leader's arrow to another block, the text associated with the new leader took on the name of the new block.

However, I can't find where this process was described.  Any ideas?

-Joe