engine diagnosis help – Locked motor?

had a long version written and my laptop did dumb things. here is short hand.

i went too deep. like 20′ deep for about 30 minutes. drained the motor, both diffs, trans and transfer case. pulled the plugs and ran diesel through the top end, the crank case and put fresh oil in it along with a filter.

it ran for about 30-45 seconds. about the time i wanted to kill it, it acted like it wanted to die so i let it. i dumped the milky oil and filled it back up and went to start it. i can hear the starter make a weird noise, but the motor doesnt turn.

any way to verify that the motor is locked? where can i grab onto a crank bolt?