[89lxinwky]

Port them first then take them to be machined for the bigger valves that way they can clean up the valve seats that might get damaged from porting. Definitely pay the small fee and get access to the articles on fordmuscle.com. I did this and it helped tremendously. Do a search here and that will help also. I asked some questions a few months ago before porting mine. Definitely grind the thermactor bumps flush with the roof making a smooth transition to the bowl. You can work on the valve guides by grinding them down a little and tapering them like a teardrop but that takes a lot of time. You can also open up the port openings a little but probably not too much because you don't want to loose velocity. Do the searches above to find out more specifics or email some people who have done it.