I would suggest that before you even try to see if it turns over, pull the air horn and make sure the carb isn't full of debris and then pull the plugs and give each cylinder a good shot of PB Blaster or something similar, followed by a couple tablespoons of Marvel Mystery oil in each. Only then try to turn it over with plugs still removed. If it does have some cylinder rust, it will reduce scuffing by the rings and also free them up.
Easy to rebuild, but don't count on that increasing the power much-nothing to speak of there even when in perfect shape. Best rebuild kits are those for a small block Chevy