transmission EXPERTS, need help with swap!!

ok, i got the new manual tranny up on all its mounts (3) and the bell housing is about 1/2" from the block. i dont want to go ahead and close it up, because i'm really scared the drive-shaft (the axle inside the bellhousing that the clutch connects to) isn't fully engaged to the clutch. my question is, how can i be sure the drive-shaft is connected? -- i got underneath and went to the inspection cover, where the lower quarter of the flywheel is visible, and i tried to turn the flywheel with a rod, and it couldn't turn. i didn't try too hard, but does this mean they're connected? i dont want the teeth to be off.

different quick question: with the tranny, off the car, all by itself (the 5spd one) and in neutral, i could only turn the drive-shaft one revolution by hand before it just stopped, and i couldn't turn it anymore. even in a gear, same story. i know an engine has a lot more power than i do, but shouldn't i be able to spin it all day by hand?