Large edit to record dropdown

I have nearly 300,000 different records, I need to edit a dropdown field and setText to a certain value. Is there a quick way to set a record's dropdown value without having to load the record each time? I've tried to use

                 var id = record.submitFields({                      type: record.Type.SALES_ORDER,                      id: 6,                      values: {                          memo: 'ABC'                      },                      options: {                          enableSourcing: false,                          ignoreMandatoryFields : true                      }                  }); 

but it doesn't work with setText as far as I've attempted.
I tried instead of value
text: {
custentity151: value
}