Right-click on the file. Choose open with.. / choose program, and then select WinRAR from the list. If it isn't in your list then browse to where you installed WinRAR and choose WinRAR.exe as the program to open rar files with. Check the box beside: Always use the selected program to open this kind of file. Click Ok.
Now WinrRAR should be the default program to open RAR files.
Ok, I got it to work now. Thanks for the help guys. BTW, the lights look great except I think the rear blinkers should have a bit more orange in it. Other than that, it looks great.