Changing a Related Field to a Multi-Select Text field is not a good idea. A Multi-Select Text field is just a static list of options that are intended to rarely - if ever - change. If you need to have multiple records from Table A associated with Table B, generally speaking, you would want to create a 3rd table, that would be a Child to both Table A and Table B.
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Blake Harrison
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DataBlender - Quick Base Solution Provider
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