This question is for a Mustang so if not allowed, please delete but I know there are some very knowledgeable techs here so I'm hoping I can find some help.

I changed the Heater core in my 2000 Mustang. Everything works as it should but I had a part left over and I don't know what it is.
It fell out of the center section of the dash when I pulled the dash back to get to the heater.

There is a part number: F8ZB-63045G90-AA

Hope one of you guys know what this is and where it goes.

 

looks like a diverter of some sort, or maybe part of one of the blend doors.

 

If the listed number is cast in the part itself chances are its an engineering number, not necessarily a Ford part number. Sadly those aren't really helpful tracking something down.

Your best bet would be finding an exploded drawing of the heater core and duct work systems---it should be visible or listed there.

Not much direct help I know so sorry 'bout that.......

 

Thanks.

An exploded view drawing of the center section of the instrument panel would be a great idea. Hope I can find one.