I replaced the parcel shelf speakers today. The guide above is a massive help. Lucky I don't do that for a living, took 3 hours... but 6 inch speakers fit easily so don't sweat trying to find 5.25s. Rear seat bases and backs need to come out, plus parcel shelf and seat belts anchors, oh and some of the boot trim. Also some soldering to retain the original plugs. difficulty rating about 3/10. Fifty bucks well spent I say! The speakers that came out were basically dust and a magnet. Amazing they made any sound at all!
That's the mids and the rears done.
So next time she throws a CEL and won't go, at least I will have some reasonable sounds until the tow truck arrives!