My 64 used a stock bracket with a rubber bumper in front that "wedged" into the form of the dash. I stuck that bumper on one of the brackets that came with the dual speaker setup. I then made two simple angle brackets (one each side) to mount the rear of the speaker to the firewall. It holds quite well, but fair warning...I find that the audio of these dual speakers is terrible. I also have kick panel speakers that do the real job.