The problem isn't with the posts, it is with the depth. The stock radio is so shallow nothing I've ever seen comes close. Was the car you installed this in an air conditioned or non-a/c car? And Jerry, about checking your 78 A/C car dash, wouldn't that be a moot point since the 78's have an updated dash? Do your earlier cars with no A/C have a duct behind the radio area at all?