Has anyone replaced a dash speaker in a 66 with air conditioning. Can't seem to get the speaker out. Car has 283 and a bench seat. Radio is out. There is still a defroster duct (y shaped about 12 x 16 inches) and dash vent (about 1 x 8 inches. Dash vent would do it but it seems to not want to move even with the 2 screws out. Does dash vent simply push out - don't want to break it if if other screws are hidden somewhere. Thanks.