1968 Dart sudden rear end noise.

only the 66 and earlier ones. IIRC they are an inch wider on the perches, and an inch wider on the track-width, which seems to be close enough.
But my memory may not be all that accurate.
they're actually about 3" wider WMS, but you are correct in that they're only 1" wider on the perches.

which some people fake it by just pushing in the springs. but that's some back yard hackery bobo ****.

so you need really deep backspaced rims to run them on our cars. not an ideal situation for this dude.