Not sure which part you're talking about. As far as the shifter boot, trim ring & the covers for the trunk, I think Dart & Valiant parts are the same & the problem with mine is that I don't have them.
The part in the picture is only on 1964 Barracudas & (I think) some 1964 Valiant Signets, with manual transmissions. I've seen two styles, a narrow one & the big square one like I've got pictured. The one in the picture is my one good one that took me a while to find. I cut my original to mount two 2" gauges in a long time ago. I'm thinking of cutting the one in the picture to mount a 3 3/8" tach in but don't want to cut the only good one I've got. So I'm looking for another good one so I can use it if I decide later on that I don't want the tach there. I'm just trying to cover all of my bases.