Good info thanks for posting. I replaced the ml amp earlier this year and probably will do the sub soon.I installed an 8" JL 8W3 in the factory enclosure. I am powering it with an Alpine 600.1 sub amp.
The enclosure seems to be holding up fine but I am getting some rattling at certain frequencies. Part of that is coming from the fact that the grill cover is just tall enough to be pushing on the panel and not letting one of the clips stay in place. I can't remove the cover though since I have to build a 10" to 8" adapter so the sub already sits higher in place.
I may take it back apart and add some CLD to the actual enclosure. I had already added some to the quarter panel since it was being vibrated by the stock ML sub.
Over all I am pleased and surprised by the amount of bass from this setup. On certain songs I am able to shake the rear view mirror to the point it is completely unusable.
Once I get some type or drawer system in there I can move the amp and processor to that and pull out the box and 10" Alpine Type R sub and gain back that room.