Chevy 3 speed with overdrive

I picked up two of these tranys a few weeks ago. Any idea if there usefull for anything? The overdrive works off a cable pull with a solinoid and govener hanging off the side of the tail housing.

I'm just looking for years, overdrive ratio, type of info. Websites and such. Thanks.

 

http://www.jalopyjournal.com/forum/showthread.php?t=134582&highlight=overdrive

 

sweet thanks.

 

Is it an early (55-62)or late three speed? The late are all synchro in all three gears. the neat thing about them is the mainshaft is the same as a saginaw four speed and the od can be put on the four speed for eight forward gears.