I'm just testing it out, so I fashioned a retainer out of Tesa tape sitting on a bed of poly fil. It works fine for a few weeks.How did you mount the tweeter in the dash? Did you need some type of adapter?
I'm debating upgrading my components from the Focals to something nicer. I've actually been impressed by the Focal woofers, but the tweeters leave a lot to be desired. They feel cheap and sound tinny.
Once I figure out which tweeter will go there long term, I'll get a pair of these.