All the ones I've seen have provision for it in the casting. If it is drilled, crossdrilled and plugged it is a sideoiler. No side drilling will have the
oil going through the top centre of the block known as a topoiler or centreoiler. The boat motors are nice as they don't suck road dirt and usually have a good bore. The other advantage is the heat cycles are long and consistent not like a 2 minute trip to the store. As long as they haven't been run in the salt water!