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Far ultraviolet emission lines are fundamental to interpret the ionized interstellar medium (ISM) properties of the first generation of galaxies that will be observed with the James Webb Space Telescope (JWST). The COS Legacy Archive Spectroscopic SurveY (CLASSY) HST-COS treasury program provided the first high-resolution spectral catalog of local high-z analogues to investigate their stellar and gas properties to improve the diagnostic power of UV lines. However comma in order to fully understand the physical conditions that give rise to their excitation comma we need to spatially tackle these diagnostics. This will allow us to trace their spatial distribution and to isolate the origin of the UV photons within these systems. Here we propose to obtain emission line images down to virgul10 pc resolution comma using the high resolution imaging from ACS and STIS comma of three nearby well-known low-metallicity starbursts selected from CLASSY. These sources are remarkably characterized by strong CIV1548 comma 1551 comma HeII1640 comma CORCHETE_OPENOIIICORCHETE_CLOSE1661 comma 6 and CORCHETE_OPENCIIICORCHETE_CLOSE1907 comma CIIICORCHETE_CLOSE1909 comma and by different Ly-alpha profiles. The powerful combination of available optical integral field spectroscopy data comma archival and new HST observations in concert with state-of-the-art models will allow us to investigate and interpret the morphology of the emission line diagnostics. Hence comma not only we will be able to track the ionization source(s) of the gas and the ionization structure in our targets comma but also test indirect tracers of leaking ionizing radiation (i.e. comma Lyman continuum escape). This study will provide us with an extremely powerful toolkit comma pivotal for understanding the ISM conditions of the earliest galaxies.