I am going to install this setup and understand everything involved except one issue. I am adding saddle bag lids and speakers so my bike originally did not have rear speakers. With this being the case I do not see how I would install the rca input line leveler on the rear it appears I would just run the speaker wire straight from the amp to my rear speakers? My system has already been flashed to open the back speaker ports do to I am replacing the Harley Boom Amp Thanks for any info