Figuring things out on a 92 hatch I just bought with a b20b high compression swap and gsr trans.

Checked the ignition timing and the guy had it basically advanced to the max. I adjusted it back to 18 degrees but could not find the plug I needed to jumper wire to stop the ecu from adjusting it? It did not seem to jump around at all though so makes me think the ecu wasn't messing with it at all. It stayed rock solid. Which leads me to my next questions.

I saw it has a skunk 2 ecu, how do I tell the ecu has been tuned for? Also, 18 degrees before tdc will yield me the most power correct? I'll be using high octane fuel

Thanks for any help