I find Lewis Bush in Co. "B" of the 3rd Reserves Battalion (not regiment). If you do a search on "3rd Reserves", you should find other information in the archives of this board.

However, the 3rd Battalion was possibly consolidated with the 4th Reserves Battalion to form, briefly, the 65th Alabama Regiment (March 1865, but there is some question about this). They were then captured at Girard in mid-April 1865, having helped in the defense of Mobile, and against Wilson's Raid.