After bridging TE and E, start engine, set the ignition timing, off engine ..... will the ECU still keep the new setting if battery terminals were disconnected ?

Is it necessary to ground the ECU ( metal casing )?

While lengthening the O2 sensor wire, I notice there is a thicker silver wire inside the bunch of copper wires, not supposed to be cut?

Anyone fabricated the turbo actuator-wastegate rod to adjustable? ( something like a steering arm, can lengthen or short without taking the cir-clip and actuator off ) Please post a pic. Brain not working properly, just can't figure out how to do it, was thinking of using wire clamps but having thread allows more precise adjustments.

Thank you in advance