Here is one of my favorite conversions.
The base is the battery operated Ertl one
http://i403.photobucket.com/albums/pp118/Britainsfan/8960swe3
http://i403.photobucket.com/albums/pp118/Britainsfan/8960swe4
http://i403.photobucket.com/albums/pp118/Britainsfan/8960swe5
http://i403.photobucket.com/albums/pp118/Britainsfan/8960swe6
http://i403.photobucket.com/albums/pp118/Britainsfan/8960swe7