The only thing that is boring for me about this is lack of knowledgeYes, very valuable experience- there are standard rules about laying out a high gain (open loop) amplifier. The thing is that it is fairly pernickety and perhaps boring.
It does not matter if the amplifier is inverting or non inverting for audio amplification.
What is needed now is a description of the input signal and source and the required output signal and what is to be driven.
We do know that 12V supply lines are desirable.
spec
Dont know much about the siren (input signal) it is a analog circuit making sounds. Guess I need some more equipment than the multimeter to figure that out