Use Navigation Tools For Excel add-in to manage many models at the same time without problems. This toolbar have this useful tools:

 

Decompose Formula
Rotate through open wokbooks: Browse among many opened workbook, with one click!
Previous Sheet: Go to previous sheet, with one click!
Next Sheet: Go to next sheet, with one click!
Freeze | divide panes
 
Tools
Arrange windows
Toggle settings
Workbooks manager
Sheets manager
My favorites
Model navigator
Cell's watcher
Cell reference tracker
To do list
Version manager
Guides lines
Add to recents file's list
Erase history of files
Password list
Password list settings