For a while I have been trying to figure a way of closing the doors with the minimal amount of effort and weight, looked a various methods out there lots of good ideas. But I could not get the right actuation to occur . I did want to do a more scale look but this most simple method seemed to work well, series of photos and a few videos at the link .

https://goo.gl/photos/L5bgyFNRzZtmovTj7

No scale points here for sure but it works well- doors close tight and it is adjustable and resist a little damage if the doors are bumped .The tubing is gasoline tubing at first I used the yellow stuff but the black looks better. I suspect after a while the tubing will need to be replaced but there is no fuel running through it so that will make it last. The gear has a bit a shock system so the doors will pull in a little keeping them higher above the ground .  Over all a lot of advantages so far .