Gearbox extension housing question

["Cary Henry" <caryhenry@hotmail.com>]

I am trying to remove the gearbox extension housing from the gearbox on my 
76 tr6.  I have disconnected the speedo cable, removed the pin bolt, and 
removed the six housing bolts.  I can only get the housing to move about 
1/4" of an inch from the gearbox and then it sticks.  Is there something I 
am forgetting, or do I need a hammer to persuade the housing to come off?  
Thank you for your help!!!
Cary Henry