Re: mk6 headunit
I did mine this weekend. You just cut the slats, then file/grind down the stumps to make the single opening. I then put some black electrical tape along this inside lip, so you can't see any of the cut-outs where the slats were.
The hardest thing was securing the cage into the Autoleads adaptor, as the adaptor was too deep for the cage push out securing slats, so I had to Aryldite the cage into the adaptor. Another slight difficulty was making use of the rear support rail for the aftermarket hifi. As the new one is higher up in the top space of the autoleads adaptor I just used a metal strip, which then bolted onto the rail clip. I would go through this effort, as it will make sure the headunit won't sag and strain the cage.