Upgraded tweeters in a 6N2

Hello

I've got various issues with speakers cutting out in the Polo - I've checked my headunit output, which appears fine, so the problem lies either with the speakers or the cabling. I figured I'd make a mini-project out of it, do some sound deadening while the doors are apart and stick some aftermarket components in at the same time, which leads to my question:

Has anyone had any success with mounting aftermarket tweeters in the stock locations, or does everything require modification/building pods etc? I'd like to keep everything looking as standard as possible, so if any brands are better than others for achieving this, it'd be really helpful to know.

Thanks in advance

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