Updating to a new radio?

[wrs986]

I want to update the factory radio that came with my 1999 Boxster. It’s a Becker CDR 210 with an amp in the front trunk. I’m going to purchase a Kenwood BT 525 HD. Does anyone know if the amp that comes from the factory will work with this style Radio?
I’ve looked online and I see two different amps that came with this car. one is a Nokia and the other is a HAES. Both look to be the same type amplifier.
I’ve talk to an installation guy and he said until he can pull out the old radio he won’t know if the sample work or not. Something to do with the wiring harness.