Your dash frame does not appear modified, but the plastic dash cover is not correct for a 1970. The 1970 dash (1 year only) had vertical splines along the entirety of the bottom portion and under the gauges as in these samples.
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Just an FYI. Your bezel isn't proper for a 1970 Challenger. I am not saying it won't fit, but it is not visually correct. The bezel on a 1970 Challenger has ribs running vertically all along the bottom and the area immediately under the gauges is rounded, not flat.
Good morning Mayhem! You may want to move this question to the Engine Issues forum for folks who monitor that forum! Link to Engine Issues forum
And maybe put a copy in the Wanted to Buy Forum. WTB Forum link
I have the same problem with my resto project regarding the 14" wheels and wanting discs on the front. I am finding MANY manufacturers are coming out with conversion kits they say work with 14". Here are a couple I have found. Some require that orders come from dealer, so you may need to ask...