if you've only taken the bungs out
once as above then that is something you should look at more closely when rebuilding an engine.
apart from the brass bung in the head face all other galleries in the engine are simple straight holes which can be cleaned perfectly well with the proper brushes etc irrespective of what dirt or sand is in them. getting the engine 'cleanish' is a world away from cleaning it properly and in the case of this rusty block any cleaning process will introduce dirt.
removing the bungs is essential for engine preparation
once was used to show a example of me doing it one time
