Engine High Idle After New Iac, '03 Mustang Gt.

So I had to replaced my IAC valve.. My car was stalling with no check engine light traced it back to the IAC. All good right? After replacing it I started the car and it started right up, no issues, and idled at around 700 RPM. Nice and smooth. I took the car out for a quick drive and it wasn't stalling any more so I thought problem fixed...then I noticed that it was idling at 2,000 RPM. When I pressed the clutch, even if it was running at 1500 RPM, it would idle up to around 2000. At stop signs- 2000 RPM. Getting back into the garage- 2000 RPM.

I shut it off, disconnected the battery for about 20 minutes to hopefully reset the ECU. Started it up again, perfect! 700 RPM and smooth. Out for another drive and the same thing- as soon as I started driving it would idle at 2000 RPM at stop signs or when I had the clutch in and then back in the garage. Total drive distance was only about 3 miles.

Is this just a matter of the ECU still needing to relearn the idle trims with the new IAC? I don't have a garage full of auto tools to do a whole lot to it so I'm hoping I don't have to take the car in to the shop but I will if I need to.

Brand new battery- literally. Battery was replaced about 2 months ago, and terminals are tight and sparkling clean. Alternator is good too- replaced that about 2 years ago. Those were my first 2 thoughts when the car first started having the stalling issues so even thought he battery was brand new I still took it over to my local Auto Zone and had them check it out.

So do you think the high idle will clear itself after a little bit of drive time?