In the FAR's it says an instructor endorsement is required, but I called the testing center and they say neither test requires a sign off.
All good answers, in substance, but no one's giving the FAR reference that you need to continue as an instructor.
Notice the difference in the wording of FAR 61.183(d)&(e):
(d)"Receive a logbook endorsement..on FOI-61.185, and
(e)"Pass a knowledge test on..(FOI-61.185..."
..and the wording in PP 61.103(d)&(e):
(d)"Receive a logbook endorsement from instructor...
(1)"Who gave the training...
(2)"Certified that the person is prepared for the required knowledge test."
(e)"Pass the test..."
It is the (d)(2) part that is in all the PP, IRA, & Comm that specifically says "Certified that the person is ready for the knowledge or practical test that you look for in the regs. The word "endorsement" is used in many other applications not involving a certification test.
The endorsement referenced in 61.183(d) means that the training must be done and logged by a qualified instructor, but he/she has not certified that you will pass.
Go figure.