Just wondering if anyone would know if the front diff from and 2005 sportsman 700 HO would fit in a 2004 sportsman 700 EFI? The 2005 is also carbureted...

 

I think they are the same, go to bike bandit and compare part #.

 

i would agree they should be the same.

 

By looking at part numbers if the '04 was built after 7/14/03 and the '05 was built before 6/13/05 they are the same. Otherwise not the same number. But I wouldn't say that means it will not work, it may be minor changes,hard to say without looking at it or digging further into the parts breakdown.
Here is the parts catalog:
http://parts.polarisind.com/Browse/Browse.asp