1.

Getting new oil cooler.
Do I mount this between bumper and radiator?

2. I bought a used ECU for my car to have tune program flashed into it. Who do you suggest sending it to?

3. I hear Audi exhausts sound great without catalytic converter, and leave muffler. True or False?

4. Aftermarket stereo installed, but only drivers door speaker and dash speaker work. Whatvdo I need for all speakers to work?

THANKS AGAIN FOR ANY INFO!!