If you would like to keep track of which block is which in the drawing view, you can add a label by placing a data field inside of the block. Then everywhere that block is placed will be labeled. 

First, name your block with a good, concise description of what is contained in the block. To edit the name of the block, use the quick properties box when the block is selected in the drawing view, or use the Blocks dialog.

1. Enter Edit block mode from the Blocks dialog or by double-clicking on the block in the drawing view.
2. Insert the Data Field from the Tools component tab.
   
   
   
   
3. Set the variable to Block Name. After selecting a variable, you can close the dialog. If you need to reopen the dialog box, double-click on the data field in the drawing view.
4. Set the alignment and text style information in the quick properties box when the text is selected.
5. Click Drawing in the upper-right corner of the 2D or 3D drawing view to exit Edit Block mode.