I've just started porting 906 heads with the help of porting templates , however in order to match the template with the port it looks like I need to cut into the valve seat, and of course I can't do that,the top of the template hits right below the valve seat, so should I continue to grind right below the valve seat or did I make a major screw up when I started porting? BTW this is happening in two places.

 

I would say study up on bowl work for mopars. I would give you some input but I havent made it into the porting category yet for modding mills. I am still at studying the cam shaft. I am sure somebody here will know, if not read up.