Ed,
Let me reword this in two different ways you achieve what you want. First of all you are correct, there is no csv type. You don't need to have a csv file type to open it Excel.
So two options.
1. As I stated, select the 'save as' option. It will prompt you where to save the file. You can also key the entire file name replacing the file name from test.txt to test.csv and then save it. It will save it to the name you give it with the 'csv' included. By replacing the .txt with .csv, it will not save it as a .txt file. Do not save as .xlsx file type as it will not work. Then open Excel (do not double click on the downloaded file because you will get data split into columns. Browse to the location where you saved the 'csv' file and open it(be sure you change the Excel file type to open to *.*). it will see that it is a fixed length file. you may see vertical lines that would indicate where a new column starts. Remove any vertical lines. then click finish. you will have all your JILs in one column. You can then save as an .xlsx file if you want.
2. save as a text file. go to the location of the file and rename it to csv or you can leave it as txt. Then open Excel (do not double click on the downloaded file because you will get data split into columns. Browse to the location where you saved the 'csv' or 'txt' file and open it (be sure you change the Excel file type to open to *.*). it will see that it is a fixed length file. you may see vertical lines that would indicate where a new column starts. Remove any vertical lines. then click finish. you will have all your JILs in one column. You can then save as an .xlsx file if you want.
either option will work because I have done it.