cut off switch wire OD

Good evening,

Sorry I forgot to introduce myself ...

My name is Konstantin, I own a Porsche 911 type 964 C4 (AWD) from 1992, the car has an Emeral MK3 ECU, it's been remaped on a rolling road.

I am intended first to reconize and remove all the dead wiring special after deleting a few things and at a second statge modenise the wirring.

at the moment I am repairing some od connections done in the past resulting in a various issues and a none starting engine anymore, nearly there with the repair.

I am installing a 6 way cut off switch, I will be cutting connecting a wire witch has 0.5 diameter under my DME (supplying the ECU and fuel pump), his length to the cut off switch will be about 1m, do I need to increase the diameter of the initial wire in case it will lose amperage from the length, lets say going from 0.5 to 1 diametre ?

Thanks for your help

Konstantin