Is rocker backing needed?
 

If a person uses the front and rear-outer floor replacement patch panel, does the rocker backing need to be used? Or does the lower portion of these two afore mentioned pieces take the place of the backing? Also what size and grade bolts are used on the lower a pillar? Thanks for the help in advance.

No, You don't need the backing plates in you are using the floor repair panels.

Thank you Tim!

I didn't use them with my 2 trucks. It's just another place for mud and junk to collect and cause rot. I just left the back area open to breath. They are plenty strong too.