2009 Chevy traverse LS Catlytic Converter

I have gotten the dreaded P codes on my traverse. Took it to my mechanic and he wanted 1800 to replace both catalytic converters the front on and the one near the firewall. I said no. I purchased two eastern catalytic converters and have replaced the front one. My problem is that I cannot see how I am gonna get tools to the one near the firewall to get the bolts off.

Are there tricks to this or do I need to remove some other component to get to it?

Thanks