FAR 61.303. Look at the sixth line down in the table (assuming you hold a US Driver's License. It refers to 61.321, which documents the endorsements required.

As I said before, I have done this path. It works.

The hardest part is to submit the required form at the end to report the endorsement to the FAA. When I did it, it couldn't be done via IACRA. Instead, you need to submit for 8710-11. Note the -11 at the end; you can't use a regular 8710. Google it and CAREFULLY follow the instructions for the form.

Lynn Alley
"2KA"