The point of the test is to measure the distortions or third order beat under the carrier so you will never get any true information pulling lead. If you were using a 8591c you could do a 6Mhz offset test if there is no channel either side of your test carrier and that would eliminate the need for the head-end support. But the SDA does not have that optiion.
This is CABL.com posting #349337. Tiny Link: cabl.co/mbC2D