Hi, does anyone know, if I can put an original Alpine head (Harman Kardon with all the gadgets like DSP and SUB) unit sinmply plug & play into a 98 midline equipped Gems?

I have a 2001 breaker with a working unit and thinking of swapping my after market unit to a genuine one ...
Thanks in advance!

If your 98 had the Clarion it will have had a 10 way speaker output DIN plug, So the 4 channels plus the output for the sub. The Alpine will have an 8 way DIN connector with the sub output on a separate plug. Depending on how much has been changed to fit your aftermarket head unit, it might be plug and play but it might not. With an Alpine that had the DSP amp, you will need the door amps, or something to boost the output, that a mid line system didn't have, they were only fitted on the High line. Unless you intend installing the DSP amp as well, in which case it is far from plug and play, more like a total rewire.

THX Richard, I don´t have a sub ... there are DIN plugs, the aftermarket was a straight fit. What a pity, I had the fear of the rewiring, which is sadly not an option.
The Clarion units are quite pricey and there was an offer refurbished with bluetooth, but they seem now not available any more.

Adding line in and Bluetooth to the Clarion was fairly simple but the main problem with the Clarion units was the display failing and they are NLA. You used to be able to send them to Clarion who would do a fixed price repair which included a new display, adding the line in and making them code free. I sent one to them about 5 years ago and they called me to say that all they had left was grade B displays and would I be happy with one of them. I said to go ahead and that unit went in the Ascot but had started to fail by the time I sold it last year.

If you still have your original DIN plugs there's nothing to stop you trying the Alpine and see how it works. I suspect it will be low on volume without the amps but you've got nothing to lose.