The defining challenge of connecting NISQ quantum computers over large distances is efficient microwave to optical transduction. In this work, we demonstrate a new platform for piezo-optomechanical conversion by combining a crystalline silicon nanobeam photonic crystal cavity and a suspended thin-film lithium niobate acoustic resonator. The goal is to combine the excellent optomechanical properties of the silicon nanobeam cavity with coherent excitations in a piezoelectric resonator in order to achieve large effective coupling between the microwave excitation and the optical cavity. In order to fabricate this hybrid silicon-on-lithium niobate device, we explore a technique termed ‘slapping’ where a loosely connected suspended nanostructure is patterned such that a tapered optical fiber can be used to rip it away and place it in an arbitrary location on another chip. We report a single photon optomechanical coupling rate g_0 = 5.1 kHz and a single photon microwave to optical efficiency of η_{μ→o} = 6.1 × 10−6 at 25μW of input optical power in a device limited by a suboptimal optical interface.