air vent box 64 Valiant

Has anybody removed the drivers side air vent box and/or door from a 64-66 Valiant? My door is missing & broken and it seems to be a riveted to the box setup. I have a salvage lot willing to sell me the whole box, but we can't figure out how to remove it. Can't seem to find any clips or bolts. Maybe some of you Hotrodders that have disassembled these will know what I need to know.