tempur

Dear Enthusiasts, can someone please tell me (or post a picture) where to find the amplifier of the two-unit Becker systems in a Mercedes A124? The previous owner replaced the original Becker with an after-market radio and I want to return it to stock. I thought it would fit behind the sheet metal inside the trunk on the left next to the antenna (see pic) but now the covering no longer fits. A second amplifier (for the optional Active Bass System) is fitted on the same side so I thought it would make sense for both to be near each other.
Thanks for your help,
Tempur