Repairing Grundig Satellit 3400

Question

The amplifier section of my Grundig 3400 is not working. Checking on the amplifier section I found two Transstors bad and replaced it with BD433 and BD434, However it still neddssome work and I cannot release the amplifier section. It looks like a s***w holds it back in the middle of the right side, which I cannot find. Could you show me how to release the amplifier section without breaking the plastic hold? I am in Venezuela about 5000 miles and two borders from any repair station.
Thank you for your kind help.
Thomas Koppel
YV5TK
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