Yes, SPOUT wire/signal needs to be disconnected to set Base Spark timing, same as you needed to unplug vacuum advance to set Base spark timing on older distributors
So there is a SPOUT Connector for that purpose, basically a Jumper that you pull out to set Base timing
O2s are the only sensors that wear out at specific times, 100k miles or 12 years
They use a chemical reaction to generate voltage when heated above 600degF
And they simply run out of that chemical
At end of life they produce less and less voltage, which means "lean" to the computer
0.1v = lean
0.9v = rich
So a false lean, and computer runs engine richer than it should which costs you lots of money over the years in wasted fuel until O2 finally sets a code when its "dead" or your MPG gets so bad you investigate why, lol
So always a good idea to change O2 sensor if its over 12 years old or over 100k miles since the last change