Before getting stuck into the tricky stuff, there is some easy search/replaces you can do that will help:

• Remove any ; at the end of lines, e.g. use regular expression find ;\s*$) and replace with empty string.
• Remove instance methods -, e.g. regular expression find ^\s*)-\s* and replace with $1func.

Also remove any *'s because Swift doesn't need them to identify reference vs. value types. This is hard to do safely with a regular expression because of the obvious confusion with the multiplication operator. So do it manually and with care.