Hmm, something is not right there.
The D1 bracket should slide perfectly into the rail for the stock radio.
The top and bottom of the bracket have small lips, they should come right up against the flat piece where the stock radio was bolted onto.
The plastic dash piece with the defrost/tract/fog light buttons should go in front of the D1, not behind it.
In the picture I attatched you can see the stock radio rail, the bottom of the A/C Controls, and the bottom suport piece that the stock radio bolted into.
The Bracket for the D1 should be flush with all of those surfaces, push it all the way back, and fold the tabs down.
I didn't use any mounting kits, just the bracket that same with the D1.
I tried making a diagram.
Hope that helps.
Jason
Attached Files (2)

mustang dash apart.jpg

mustang dash apart diagram.jpg