WARNING: The bellhousing bolt pattern and starter location is different, see post #8, in the following link, for a picture:
http://www.4btswaps.com/forum/showthread.php?10506-Russ-s-M5R2-thread
For a general reference on Ford bellhousing patterns:
http://en.wikipedia.org/wiki/List_of_Ford_bellhousing_patterns#Later_Windsor_V8_pattern
Notes:
1. Most Cummins-to-Ford adapters were to replace the Ford 300 CID straight 6 cylinder engine. These adapters used the "Later Windsor V8 pattern"
2. I believe that the 1999-2002 F150 had the "Modular V8 pattern" engine. Spend some time researching before spending your dollars.
3. I am running a 4BT with the "Later Windsor V8 pattern" Cummins-to-Ford adapter. My M5R2 came from a 1997 F150 that had a "4.2L Canadian Essex 90° V6 (RWD only)". The bolt holes were metric and required a light clearance drilling with a 3/8 inch drill to use the bolt holes on my engine adapter.