I haven't ported any LSx heads yet but will be in the next week or so. The main thing I can see that can be done is cutting out the nub on the roof of the port. It is the bottom of the rocker bolt hole. You will expose the hole to the port but this is common practice on all types of engines. Also the valve bowl(under the valve) can be cleaned up a little, mostly around the valve guide area, it can be thinned up a little. Other than that I'd just smooth everything up with a sand roll. Might could gasket match if they need it??? A 3 or 5 angle valve job would help. That can get a little pricy though. Maybe some LSx porting experts will chime in.