For most Mark 2 models before 2005, it can usually be found on the front of the engine block, beneath the intake manifold or to the right of the water pump. It may be stamped directly onto the block, or on a metal plate attached to the block.
On some later Mark 2 models, the engine number may be found on the rear of the engine block, near the oil filter. It is typically stamped into the block itself.
On certain models, it may also be located on a sticker or tag in the engine bay, typically near the top or bottom of the firewall.
Please note that the specific location and format of the engine number may vary depending on the exact year, model, and engine variant of your Mark 2. If you are having difficulty finding the engine number, it is recommended to refer to the vehicle's owner's manual or contact your local Toyota dealer for assistance.