It is impossible to fit wiring wrong as they are keyed so I don't think you have done it wrong. Did yo have the other speakers working ok with your old radio? Was the previous radio a Volvo one? If so, swap the old radio back in (they should all be compatible with the amp wiring) and see if you get ...

dad2three wrote: ↑21 Jun 2020, 17:35 When it is all hooked up the 10 pin harness from the car is not used, correct?

Good News!
That’s where the outboard amp ties back into your 4 corners of speakers,
so you’re day is gonna get a whole lot better when you plug it in.

Hope it fixes the issue. That's what always make the effort worthwhile.

Good Luck!

Neil.