I have my dash rolled back right now so I could change my front speaker and also access the factory tach to send it in to be updated with the modern technology. My windshield is currently out so it is a lot easier for me to work on. Here are a few pictures of the bolts (there are 5 of them) and the clips that they screw into and yes they are 1/4-20 bolts you use a 3/8" socket to remove and install. I hope these help you.
Bob
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