Convert wk3 to xls
In windows XP, I converted wk3 to xls by copying from Lotus 1-2-3 and pasting into excel. I'm sure I lost functionality, but for most files it works OK. Lotus 1-2-3 won't open in Windows 8. However if I simply change the 3 to a 1 in the file name, Libre Office Spreadsheet opens them and then converts to xls. Again I suspect some functionality is lost.
Let me know if you find a better way to convert.
File conversion @ wikipedia