In need of advice on adding a 5 Channel Amp to a 9.2 Set-up

Currently running my 9.2 HT with with my Yamaha AVR 3060 rated at 165 W 2 channel @ 8 ohms, 0.9% THD @1khz and 150 W 2 channel @ 8 ohms, 0.06% THD @20hz-20khz. In my closet I have a B&K AV5000 series ii 5 Channel amp rated at 125 Watt - 8 Ohm - 5 channels and 185 Watt - 4 Ohm - 5 channels. The 2 mains are Sonus Faber GP Home @ 6ohms. Center Channel is a JBL Stage 125c @ 6ohms (Sitting in that same closet is the Sonus Faber GP Home Center channel speaker). Surrounds are Klipsch Synergy 2 @ 8ohms. Height Channel speakers are Polk owm3 (2 pairs) @ 8ohms. And the the .2 are dual SVS PB2000 pros.
If I were to add the B&K to the mix, what would be the best option? Put the front 3 with the B&K and let the Yamaha handle everything else or include the surrounds on the B&K to take away some of the duties for the Yamaha? Or any other recommended configurations.

So you have a 5.2.4 system? I don’t know the power amp you have, but I think I would move all 5 main channels to the power amp, and let the Yamaha only drive the height speakers. Specially if the power amp is a known sturdy well built amp.

Yes I guess that would be a 5.2.4 set up. That B&K was made in 1997 and has been reviewed as built like a tank and has underrated power listings.

I would hook it up to all 5 main channels then😄. If you like me have everything hooked up through the Yamaha, you leave the power supply on that one to process audio and video, and the comparative light load of the heights.