My '68 already has a modern single din head unit installed. Would this radio work in that space or does the dash need to have the original size cutouts?

• I purchased a 1977 Bronco and it has one of these Radios. I don't have a Manual for it. Can I purchase one? general
• Looking for demensions of radio. Will this interfer with air box? general
• Can you give me the dimensions of the faceplate. I want to make sure it will cover the cutout in my dash. general