Hi Howard,
Good Day!
You might wanna declare another internal table instead of using "IT_OUTPUT" since you cannot pass the content of the internal table "IT_MAIN" to a field object(table structure) which is "IT_OUTPUT". You can also use internal table "IT_MAIN" for your FM "REUSE_ALV_GRID_DISPLAY".
Please <removed by moderator> and follow me if found useful. 
Best Regards,
Charlie
Message was edited by: Manish Kumar
