New to me S6 Avant - no start

[Bares, Vittorio]

I've located my no-start condition - it has to do with a badly corroded
positive lead cable from the battery.

 

I started cutting  back the sheathing and it has corrosion at least 6
inches back and more.

 

Do I keep cutting it back until its clean - then use a butt connector to
splice back the length I need to the battery?

 

Or...is this a scenario where I should replace the entire length to the
starter?

 

Thanks,

 

Vittorio -