If you run ramcharger scoops, are you going to do it right and set up the entire airbox system under the hood with the air cleaner base, etc? If not, I'd leave it be. It only cheapens the look of the car when the hood is open if it isn't done right.
Honestly, I think the monochromatic look of the car with the painted top is nice. The car looked good with the trim and vinyl top, too.
I don't like bumblebee stripes on anything newer than 1970, because I know it's wrong. Such as the same, I'd never paint my '68 Charger a high impact color.
I honestly think keeping the '71 taillights will give it the distinction of the year of your car. I like the look of the '70 taillights too, as that's what my GF's Scamp has by default, but the designation of a '71 Dart is the combination of inset side marker lights, divided grill and 4 taillights. If you start playing with that, it kind of bastardizes the car into a custom, which is ok in it's own right, but confusing as well. It will pass as a '70, only having the badges on the fenders, rather than back on the quarter panels.
I'm also certain that a '70 Swinger was still a high performance package, wheras '71 was a 318.
Don't worry about clips on the top, if you want one. You don't need to rivet new clips on, in fact, it's a bad idea on new paint, as the rivet expanding can crack the paint and primer and filler, if any small amount was used. Just drill holes and use a good seam sealer on the inside of the C pillar after installing the clips and mouldings. You can get to all of them.
Painting the top a different color will not make anything easier. You still have trim to remove, which should be very easy, considering the body shop already did this when they took the top off to paint what you have. It's as simple as using a hook pic tool to pull the clip from the glass side (not the paint side) and releasing the trim from the clip , starting with the bottom pieces. You can take that trim off in a matter of minutes. Just get a picture of the window clip and study it. It stays on the tab, on the car and simply bites the edge of the trim that sits against the paint, so you just pry it away from the body, toward the inside of the trim and it releases.
I don't think the car needs a top, but I do like them. I'd go with a white top and white interior, because it looks classy. Not a Dart, but the color and package is sweet on this rig. -
[ame="http://www.youtube.com/watch?v=xhESSIcnFLo"]Plymouth Scamp 2009 - YouTube[/ame]
You could go black and white on the interior. I did black and white on the Scamp with a black top, black dash, black carpet, white upholstery, white lower door panels and a white double pinstripe on the 2nd body line on my GF's car.