access/courses - Combine fields containing redundancy

I have imported data from Excel to Access and hence have a very wide spreadsheet with lots of columns (each a different project name) with 'x' marked to denote if affected. The training manual recommends combining fields - to build tall not wide (page 4 of Access Intermediate Training Support Pack). I therefore think I need to replace all the vertical columns and add a new record for each cell marked 'x' listing the detail (ie, project name).

There are a lot of 'x's across 400 rows and about 20 columns. Is there an easier way of combining the data or do I need to copy each line with an x in it into a new record and just add the project name field (I suppose I could use a look up table to make that easier) but think it will still take a very long time.

Thanks
Karen