I mean yeah, anything is possible.
By far the easiest way to do this is to buy the rallye dash frame to go along with the rallye gauge cluster. As pointed out the '70 has a thumbwheel radio, the '71 does not, so if you want a '70 you will need the '70 cluster and a '70 dash frame. '68 and '69 also had thumbwheel radios, but, they had the ignition switch in the dash too so the frame is different. I suppose you could also use a '68/69 cluster, but, there would be some differences for the cluster as well. It would fit in the '70 frame though.
Or you could do it the dumb/cheap way like I did, which was modify my '74 Duster dash frame to accept the rallye gauge cluster. I don't recommend this actually. The radio mount in the dash frame is not in the same place between the standard gauges and the rallye gauges, it actually shifts over ~1". Which means if you convert your dash frame you either have to section the radio mount in the dash frame and move it over, or run without a factory radio. I run an aftermarket radio anyway, so I did the latter. There's also the mounts for the cluster you have to add, I skipped a couple because I modified my cluster as well.
What I did is documented in my build thread, it starts at post #18 on the first page and mostly wraps up on page 3.
[URL="https://www.forabodiesonly.com/mopar/threads/my-new-74-duster-or-why-i-need-a-project-like-a-hole-in-the-head.198098/#post-1969905973"]My "new" '74 Duster- or why I need a project like a hole in the head[/URL]
Here are some of the highlights. A '71 dash will likely be HARDER to do, because the original cluster opening is smaller. Also, if you are committed to the swap over, I have a bunch of rallye dash gauge parts. Gauges, heater controls, etc. If you have the original '71 GT cluster and trim, I would be interested in it. I have a couple of '71 GT's as well.
