Radio mounting strap and AC clearance question

[msg]

I have a 66 and no radio or speaker. Im looking to get this Custom Audio Sound radio

https://customautosoundmfg.com/produ...t=cam-chtk-740

and a speaker under the dash like this

https://www.classiccarstereos.com/ki...t-speaker.html

I have no idea about what kind of room I will have in between the two devices and if it will have clearance for the AC center vent. Anyone had an installation done with these type devices? The instructions that Ive seen say it comes with a mounting strap that needs to be mounted to an existing bolt or screw on the firewall or dash. I get the feeling I will have to modify the strap or fabricate a bracket from the speaker to the back of the radio.

I had seen this bracket in a pic posted by Woogeroo some time ago. This made me wonder if this is the shape to the bracket/mounting strap I would need to work past the AC vent box and hoses and such.