Firewalker
CarAudio.com VIP
I use 4 gauge back to my distribution blocks and then 4 gauge back to the amps. 10 gauge power/ground wire is useless so if anything swap it out to 4 gauge, and yes going to 1/0 is always better if you can afford to do it and as long as it is OFC of course. If you do that then do as you said 0 gauge back to the blocks then 4 gauge to the amps. But regardless get rid of the 10 gauge