I'm making slow progress. Got the door trim off, and see the stock speaker attached to a nylon frame. My new speaker is about 5-10mm smaller in diameter than the stock. Is it better to:
(i) make up some steel brackets (or maybe use mdf?) to screw it onto nylon thing, or
(ii) ditch nylon thing and make larger, thicker MDF thing to replace whole nylon speaker mount?

I hope I'm making sense.

Other Q is re soundproofing: easiest would be to just stick something on top of the factory plastic membrane and stick the door trim back on, but what thickness could I get on there and still get the trim back on? Or is there another way?

Waterproofing is not going to be an issue, dry as a bone in there.

I really appreciate all the great advice from everyone on this forum.

Peter.

Best option is certainly to use an MDF template to replace the plastic mount.

These are templates I made a while ago that will work. Just print, paste and cut.

http://img208.imageshack.us/img208/3843/baffle1.th.jpg (http://img208.imageshack.us/my.php?image=baffle1.jpg) http://img208.imageshack.us/img208/7564/baffle2.th.jpg (http://img208.imageshack.us/my.php?image=baffle2.jpg)

In regards to soundproofing, I'm not sure what you mean? Do you mean to reduce vibrations and road noise, such as dynamat?

If so, you would remove the original plastic membrane and virtually cover the entire door with dynamat (or the like).

There are many ways to go about this (good and bad). Try searching 'dynamat' and have a looksie at what other members have done.

*12-18mm MDF for the baffle to hold the speaker
*6-9mm MDF for the service holes
*electrical tape for the loose wires
*dynamat the inner and outer skin
*something like Dynazorb or Focal Plain Chant for behind the mid bass driver

That will improve the midbass a fair bit!