Accessing Radio Connection In a 1969 Valiant

I need to remove my dash panel so I can access the power and speaker wires of the radio in my '69 Valiant. Are there any tricks I should know of---clips, hidden screws, etc...or is it fairly straight forward with a few exposed screws? Does one end need to come out first or anything like that?

Also, is the original AM radio power cable in the dash compatible with new radios or is it some strange old-school connection? Any replies are appreciated. Thanks a lot.