Were both the shifter and drive in forward gear when you reassembled the drive? If not, the shift shaft was probably not lined up, and might be bent now if the drive got forced back together like that.
Looking at that photo it lookes like the shift cable if off alinment, the push in button on the switch should be as center as you can get it in nutral with the V, it look like it is activated right now, at this point my guess is the shift assy is out of line on the drive to where it hooks up to the bell housing assy. when you pulled and reinstalled the drive was it in forword gear? if not you bent the shift shaft assy.This is the switch I'm talking abhttp://forums.iboats.com/attachment.php?attachmentid=29615&stc=1&d=1244023601out guys..