I'm not much on reading trim tags, but I have seen two tone 65 impala's. The ones with vinyl tops and ones with painted tops that use the same trim as the vinyl top to separate the colors. The convertible would be two tone by the different color of the top.
I have seen 65-66 two-tone seperated at the trim line and looks pretty good. Body lines are defined better but relies on stance importance. Simply by cutting away one turn of front coil spring or drop spindles, which is much cheaper than full airbags at 4k for the good ones.
It's a hybrid Paul that was for sale on e-bay. They stated it was non-ss but trimmed it with a few ss pieces. They might still have it(asking too much...lol) you can see the name of the dealer in pic. Jackson