another wire size list

From the battery to the d-block, what size wire should be used if the amplifier(s) maximum draw is 300 amps?

I will run (3) 4g wires to the three amps from the d-block.

Can the amplifiers be grounded without the need for a ground d-block? I was thinking about just grounding the (3) 4g grounds normally (without block)..

Thanks!

https://www.the12volt.com/info/recwirsz.asp

1/0 gauge.  Yes, you can ground each amp individually to the chassis floor pan.