Puzzle for all! - 93 2006 Vecto Convertible audio upgrade

Hi all,

After several months of having no audio in my vehicle I am going to attempt to install an aftermarket stereo but need a little advice.

This may take a long time but here is the story so far:

I jump started my beloved vehicle and the issues started, radio does not switch on and no audible chimes:
Took it to Saab specialist who Tech 2'd it and couldn't find fault, they tried a new EHU and CD player - still no Joy, I waited for them to try a new ICM but after 2 weeks and several calls they seem to have lost interest.
I purchased a new ICM and this made no difference, I then purchased an AMP1 and changed this - still no joy.

I then attempted to diagnose where the issue is by removing the items and re-adding them 1 by 1:

When the ICM is connected I have a light on the input side of Amp1, but no light is getting to either the Front CD or the EHU. This applies to my old amp and the replacement I purchased.

Another thing to note - On a 2006 convertible Amp1 is not under the seat, it is behind the rear passenger side panel, the Saab specialist did not know this!!

Anyway, in my Eureka! moment I have thought - What if i loop out everything except the ICM and the EHU? Surely I will get my chimes back.

If this is the case then I will be able to remove the standard fitted CD and replace with an aftermarket single din unit. From here I will then feed new speaker cables to all but the front centre speaker, using the single din unit to supply the front and rear factory fit speakers. I will then add an aftermarket amp and fit 2 new 6x9 in the slots behind my rear seats, taking a feed from the aftermarket unit.

Can anybody advise if this will work????

By the way I now have a spare Amp1 - would like to recoup the £100 i paid for it. Please post if interested