The opening in the top of my engine ('99 Olds Alero) will hold a quart oil container, but it is not easy to pour without spilling, at least until the oil is able to drain from the container as shown in the photo.
Step 1: A funnel helps
Step 2: Support the funnel and the container
Step 3: Oil container and funnel on support
Step 4: No welder?
Get a suitable piece of pipe or tubing. Drill or saw a hole in a piece of wood so that the hole fits the circumference of the tubing closely. Make a saw kerf so the wood can be clamped tightly around the tubing with a screw from the front side of the wood. Screw or glue two pieces of 1 x 1 inch wood to the main piece. These will support the fixture in the engine compartment.