Should talk to BrendanTheGreat. I think he does Retrofittings.

 

Its not that bad. Longest part is waiting for the sealer to dry which takes 24hours. I did some youtube videos a few years back showing how its done. It was for a 5th gen camaro so not subaru specific but if anyone wants to see them just pm me and i can forward the links. The TRS guys are great for for pointing you in the right direction on what you need and they are great at answering questions.