After a lot of research (mostly on here) I have decided to keep my build N/A with a shot of N2O. Was planning on pulling the head off to do some mild exhaust porting. I was wondering if it was possible to get a cheap compression increase by milling the head down? Or would that cause valvetrain interference issues? I'm aware this is an interference engine as is. Planning on running an RPW stage 2 cam w/ their recommended springs and cam gear. Will also be installing head studs while the head is off. This is a budget build so trying not to touch the stock bottom end. Looking for a compression ratio of about 11:1. Is this doable by milling or are pistons my only safe option?