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The discovery of some impressively luminous galaxies in the early universe has prompted questions about how such galaxies can build up so quickly. Remarkably comma luminous galaxies appear to have built up a significant amount of dust content and shine brightly in the infrared comma as early as 600 Myr after the Big Bang. Yet comma despite keen interest from the astronomical community comma only two particularly luminous galaxies are known showing prominent dust emission at z>=8 comma only one of which shows a bright ISM cooling line. Clearly comma a larger number of IR luminous galaxies need to be identified and characterized in detail. Fortunately comma thanks to on-going observations from an ALMA large program comma far-IR observations have revealed prominent dust-continuum emission in two additional UV-bright galaxies at z>virgul8 comma effectively doubling the number of such sources known in the first 650 Myr. Given the existence of only low spatial resolution imaging data of these sources from the ground comma we propose for the necessary HST imaging to obtain a high spatial-resolution view of the unobscured star formation in the sources to match the far-IR view provided by ALMA comma allowing for a more integration view of star formation. For better sensitivity and to provide for a resolved view of dust obscuration comma two-band F125W+F160W observations are requested. One significant benefit of the proposed observations -- and a key rationale for mid-cycle time -- is this program.s significantly improving prospects for detecting ISM-cooling lines in the sources thanks to the improved photometric redshift constraints.