I have a shortblock was supposed to have been a 2 bolt VR4 engine. In trying to sell it, someone pointed out that the heads were N/A heads by the markings on them. Well, now I'm concerned about the shortblock being N/A as well. how can I tell the difference without tearing it apart? i will eventually, but I want to test Compression #s forst

Which leads me to my next question. What is a good way to turn it over enough to get a good compression test? All I have is an N/A flywheel(smaller diameter from what I can see), and no N/A trans to mount the starter to. I tried using a breaker bar on the crank pulley, but just can't turn it over fast enough or long enough. Considered using my impact gun, but even with the plugs out of the cyinders, I was concerned about breaking or stripping something. Would be possible for a 1/2 air ratchet would work?