Hi Lee,
Even I had the same issue. So instead of scorecard, I started using spreadsheet component as it reflects the exact data and formatting in the excel sheet (text colour, cell background colour, font size, font style etc) and the columns width will be automatically set according to the data.
Also spreadsheet component have some more advantages when compared to scorecard like..
1. If we make any data changes in the excel, no need of mapping it once again. We just need to open the properties tab of spreadsheet component, the data will be remapped automatically.
2. We can use different color for each column header as in the attached image.
So better you try to use spreadsheet instead of scorecard for resolving your issue.