Gonnella, D. Clasby, B. Eichhorn, R.G. Elmore, B. Furuta, F. Ge, G.M. Grassellino, A. Grimm, C.J. Hall, D.L. He, Y. Hoffstaetter, G.H. Holzbauer, J.P. Kaufman, J.J. Koufalis, P.N. Liepe, M. Maniscalco, J.T. Melnychuk, O.S. O'Connell, T.I. Palczewski, A.D. Pischalnikov, Y.M. Quigley, P. Reece, C.E. Romanenko, A. Sabol, D.M. Schappert, W. Sergatskov, D.A. Smith, E.N. Veshcherevich, V. JACoW Geneva, Switzerland 978-3-95450-178-6 10.18429/JACoW-SRF2015-MOPB041 English 182-186 MOPB041 cavity cryomodule HOM SRF linac Contribution to a conference proceedings 2015 2015-12 http://dx.doi.org/10.18429/JACoW-SRF2015-MOPB041 http://srf2015.vrws.de/papers/mopb041.pdf The Linac Coherent Light Source-II (LCLS-II) is a new FEL x-ray source that is planned to be constructed in the existing SLAC tunnel. In order to meet the required high Q0 specification of 2.7x10¹⁰ at 2 K and 16 MV/m, nitrogen-doping has been proposed as a preparation method for the SRF cavities in the linac. In order to test the feasibility of these goals, four nitrogen-doped cavities have been tested at Cornell in the Horizontal Test Cryomodule (HTC) in five separate tests. The first three tests consisted of cavities assembled in the HTC with high Q input coupler. The fourth test used the same cavity as the third but with the prototype high power LCLS-II coupler installed. Finally, the fifth test used a high power LCLS-II coupler, cavity tuner, and HOM antennas. Here we report on the results from these tests along with a systematic analysis of change in performance due to the various steps in preparing and assembling LCLS-II cavities for cryomodule operation. These results represent one of the final steps to demonstrate readiness for full prototype cryomodule assembly for LCLS-II.