Here's an update/tips and pitfalls for any other amateur DIYer on triton speaker replacement.
1. Don't waste your money on the aftermarket speaker spacers. I found that they are nowhere near as deep as the originals and they cause your new speaker terminals to pretty much touch the door frame. I used the original spacers and connectors by ripping out the old speaker, soldering a connection between the new speaker terminals and the spacer terminals.
2. Buy some of that sticky-backed foam strip used to fill gaps around doors etc. This goes around the original spacer once the new speakers are installed. Will stop nasty vibration between the spacers and door trim. The shit I used cost about $5 for 2 metres worth.
3. Tweeters... I ended up keeping the original tweeters. Aftermarket tweeters don't fit very nicely behind the original tweeter bracket. Plus you have to run a wire back to your new speakers which make things a bit messier and harder to remove the door trim in future because you can't just unplug the tweeter. Perhaps you could look into putting new tweeters on an easy connector but new tweeters didn't impress me anyway.
4. My new speakers sounded tinnier and flatter than the originals... The head unit needs an upgrade if you are just swapping out speakers. That will be my next project.
5. Put heat shrink on every connection... you will be surprised how a terminal connection that appears 10mm or more from a door frame can short after hitting speed bumps etc. When it shorts the head unit will appear to seem normal but you will get no sound intermittently.
6. Sound-deadening... May as well do this if your door trims are off... I had no experience with deadening and it was a piece of piss. Doors now close with a solid thud and it's made things quieter on the road.
7. Check the speaker wiring diagrams found on this site... get your speaker wire colours correct the first time around.
8. If you don't have a good soldering iron for the job get a "Dremel versatip 2000" This is what I bought for this and other future projects. It's an awesome solder.
That's my two cents worth... I'm no expert so like always, do your research.