Where around Brussels do you park for free?

LEZ doesn't allow many to take a car into the city anymore. What are your recommendations to park for free and for 24+ hours on the outskirts of the city, with a reasonable bus/tram/metro/bike connection?

For the record, I prefer taking public transport all the way and limit my car trips as much as possible, but I sometimes can't avoid driving because of a poor train connection.

Apologies if this falls under 'generic advice', but many posts about this are outdated, and the parkings on parkandride.brussels are mostly paid parkings.

Dankuwel beaucoup!