It's likely that you or someone else had increased the mixture to compensate for the vacuum leak. After you eliminated that leak, you needed to lean the mixture proportionately. You ain't the first.

Remember to check the vacuum advance is working correctly, and vacuum retard at idle, if you have it. I disconnected the retard side on my 1980 SC dizzy. Full advance with the vacuum lines disconnected should be about 28-30 degrees, at 3500RPM and higher. I push the mechanical advance a bit more, as it gives better torque and throttle reponse.

Congrats @kltarga

Agree with PeteKz.

Additionally I would check how many turns you need to close the idle screw (remember old setting). The basic setting is 2 turns. So fully close it CW and open it by 2 turns CCW. With this setting and a CIS in shape and correct ignition timing a CIS car should idle around 800-1000rpm. If not, there's still one or more other issues.
Also I want to point you on checking the sensor plate height and the injection start (starting the fuel pump when slightly lifting the sensor plate). This hangs closely together with the idle setting and the overall CIS and mixture control.
https://forums.pelicanparts.com/porsche-911-technical-forum/1108835-cis-sensor-plate-height-2.html#post12201501
Thomas

Yes, vacuum advance is working as PeteKz described.

I will check the idle adjustment to see if it operates as Schulisco suggested. Also thanks for the link.