I'm about to change the head unit from the Symphony to a standard din sized one.

I was told the part I needed was 6YO 857 231 B41 but when I purchased it all it was was a single strip of plastic trim .

Surely this can't be right. the differance in height and width of the stereos is quite a lot.

Do I need something else from the dealer or is something missing?

No this correct.

You clip it in then wack the single din cage in, then fit the stereo and its own facia and it will fill the gap

It is just to fill the small gap at the top - it is all you need.

Yeah-my fault when you look at the stereos seperately the look a lot different in size but put 'em side by side and theres not much difference. Thanks.

I've just swapped it using original leads.

All I had to do was swap permanent live and switched live around.(wires from Sony head unit had bullet connectors to do this)

I dont even need ariel amplifier as I was told. It works just fine. Much better sound than original.

I did the same with an old Pioneer we'd had in the wife's car back in 1998/9. Considerably better than the OE radio.

An aftermarket unit definitely gives better SQ and more "punch" even with standard speakers.

Replaced mine with an Alpine 9846r I got for £50. Result.

Has everyone done the rear tweeter disconnect trick as well?

I did this from a previous thread and it makes a massive difference.

Has everyone done the rear tweeter disconnect trick as well?

I did this from a previous thread and it makes a massive difference.

What trick?

Disconnect the tweeters in the rear doors to reduce high frequency sounds hitting the front passengers ear's (the tweeters in the rear doors affect the sound stage and move it towards the rear of the car).

From the rear speaker connections in the boot, just disconnect the tweeter feed.

Simple but effective!