Hi,
+1 on the above. Dont tear too much into it, keep it on the road instead! I have seen guys just tearing down a nice driver to give it a total restoration, ending up with an empty shell and 50 boxes of parts that sits for decades.
The best advice so far on the engine (when breaks are working) is to roll it outside, put it in 5th gear and take the help of some buddies. First, start by having it in gear, gently rock it back and forth (only push on the "forth" to keep the engine potentially moving in the right direction) and check for movement. Then you push harder and harder, until the tires are slipping.
When you feel you have nothing to loose, you cant get it to move no matter what, you could always ask your buddies to push it hard, put it in first gear and release the clutch quickly when you are at speed. BUT, that might break stuff, so be cautious!!!
If the engine is frozen, my guess is that you will break the crank pulley bolt before it moves. Ask me how I know....
Regards,
Johan