In order to reach the .04 eV sensitivity to the neutrino mass that Project 8 has set as its goal, precision magnetometry of the background magnetic field is vital. Project 8’s novel measurement method, cyclotron radiation emission spectroscopy (CRES), will take place inside a cryogenic cavity at high fields, and will require magnetic field stability at the .1 ppm level. Nuclear magnetic resonance (NMR) magnetometry with hyperpolarized Helium-3 may provide a sufficiently precise probe of the field inside the cavity. This presentation will discuss the metastability exchange optical pumping (MEOP) technique necessary for this, and the challenges of implementing MEOP, Helium-3 NMR, and CRES simultaneously in Project 8’s cavity demonstrator at the UW.