I don't know the inside diameter. I guess I can remove the Driverside and measure. Or try and match it up at a hardware store. I was hoping maybe someone had an extra one sitting around somewhere.
Looking for 1 c-clip that holds the dash vent flap to the linkage. I'm missing one and I'm unable to open and close the passenger side dash vent.
Looks similar to this.
This is the vent and you can see the linkage rod/handle below the dash.
Some here. Don't know if they are 510 though.
http://community.ratsun.net/topic/27160-z24-carbed-and-some-parts/page__p__394843__fromsearch__1#entry394843