Single Engine rating add on

[Dynamo78]

Hi there,

I have been flying mil jets for the last 15 years ( T-38 and such)
While in Texas, I did my ATPL on a Piper Seminole, including removing the centerline thrust restriction.
While it is still several years until I change into civilian life and might use this, I would like to rent a plane here and there.
Single engine is much cheaper though. How does one add on the single engine on the ATPL license?
I think I know the answer ( flightschool + checkride), but would like to know from somebody firsthand.
I do not have the possibility to get it done via Mil Comp, since I am not working with the US military anymore.

Thanks for the answers.

- Dynamo

[What Now]

I did this last year on my JAR licence in the UK. Really straight forward. I went to the local flying club and met the CAA examiner who had a chat with me about what I am currently flying and looked at my logbook. He handed me the pilot's notes for the Piper Aztec (I think) then the next week I came back and flew a flight test with him. Done.

In the UK it is training at the discretion of the Chief Instructor and a test. In my case there was no training.

[Dynamo78]

That's good to hear. Anybody able to confirm the same with FAA?