whirlpool washing machine filter

Just bought one of these after our old whirlpool washer became uneconomic to repair

The instructions (instructions for use .pdf) say to use a piece out of the soap drawer to remove the plinth to get to the filter. For the life of me I cannot work out how to do it. I've tried as shown in the book but I don't want to force anything in case I break it

Anyone got one and managed it?