My van is a Syncro and has a different mud flap arrangement than your 2WD. But after taking a look at the vendors' websites, it sounds like you have the set up that GoWesty sells. They are showing just one photo and no video or instructions. It appears there are two rubber grommets that go in the holes on the wheel arch. A threaded pin goes through the hole in the mud flap and into the grommet. 
They sell the grommets for $1.95 each. The pins seem to only come in a kit for two flaps with all the  related hardware.
The other vendors sell kits that use a series of metal clips and bolts/nuts/washers. I don't know if they sell separate pieces.
I hope this helps.
Steve 

    On Tuesday, July 26, 2016 7:47 PM, Eric Caron <ecaron1@COMCAST.NET> wrote:
 

 Hi Folks,

        When my van was painted the other three OEM mud flaps were put on.  these match the one for the propane tank.  My passenger front is loos.  There is a pin coming out of the flap at the top along the body.  There is a whole in the body of the van and a plastic plug or at least a tiny part of one on the pin.  the whole in the van is empty or perhaps I can just feel the edge of a metal insert flush with the body. 

Can someone familiar with the flap tell me how it attaches to the body and how I might attach this one again?

tips, and descriptions appreciated. 

sadly web diagrams and videos don’t help in my case.

thanks folks. 

Eric Caron 
85 GL Auto Westfalia