71 Dart swinger!

The 360 wouldn't have been an option in that car. Either a slant six or 318. (Up here in Canada they made a handful of 1971 Swinger Specials with the 340 for a local Edmonton dealership as well as one in Manitoba "LL23H1R") 1974 was the fist year the 360 was introduced to the A-bodies, which was an option for the Dart Sport and Duster. As for the rims they could have been dealer installed.. There was either rallye rims, full wheel covers or dog dish caps available for that year of car. The only way to know is by finding the build sheet. You've got a pretty unique and rare car and I hope you keep the original colour! Looks great!

Thanks for sharing the pics and I hope this info helps. What's the fifth letter on your vin?

I also vote for keeping the slots.. They really suite the car.