I have often wondered if engine stands could be turned into a rotisserie. If you want 360 degree rotation, you will probably need to make them taller somehow, but you might get by without that. Please report how it turns out! By the way, I have a '71 I have owned since 1973 and I am a former Nissan partsman, so I know your car well. In 1971 there was a model change. The early '71 (Series 1), up to April 1971 and late (Series 2), April 1971 and up. There were mechanical and trim differences, you may need to know about. If your car has two vents just below the rear glass, it is a Series 1 (unless the hatch door has been replaced with a later one). I will soon be putting mine on my rotisserie (bought from Ea$twood), so we are just about at the same stage of restoration. I live in the Houston area, so if you want to contact me my email is rmeisenbach@hotmail.com.
Robert