Radiator came a bit loose, but it was easy fix, just push it back in.
Even though the amp was set to max gain of 36dB the tone controls seems to limit the input signal. I could only get about 5 watts when using my phone or other mp3 player. I was using 24vdc and 8 ohm speakers. Getting 150Watts seems very unlikely. I will try and add another input stage later.