[CamelY0]

The "Manila Engine" folder can be divided into separated folders to make upgrading your tabs easier. The folders that make up the Sprint Manila Engine (2.5.2012.1324) are...

Appointment Editor
Audio Manager Engine
Contact Picker
Contact Utility Engine
Email Setup Wizard
Facebook Engine
Google Location Service
Group Editor
HTC Bookmark
HTC GeoService
Message Enhancement
New Contact Card
Settings Improvement
SMS Inbox Threading
SMS Retry Service
Social Networks Engine
Start Icon Loader
Time Zone Auto Fix
VBookmark Manager

Leos (2.5.2012.1412.1) Engine contains a few extra folders which are..

HTC Birthday
New Mail Account

If you are using the Footprints tab you'll need..

Footcam
Footprints Engine
FootprintsThumbViewer
FootPrintsVE

All the files you have left over are included in the Manila Tab folders.

Keep in mind that your Start Icon Loader and Manila Core should be paired where they came from and also Manila People has to be upgraded along with Contact Utility Engine or your manila may crash.
Hope that helps for anyone trying to upgrade.

BTW All of these files can be found in my sig ;]