Hi and welcome to S.O.C
It's better to change the full bonnet really other wise you have to drill cut holes and so on
If you don't mine me asking where in Yorkshire do you live if you live near Sheffield Ash was holding a local meet tonight at his mates garage who repairs Subaru's. Might e able to help you :)
Impatient yep I fall in to that category too, so don't worry ;)