Gasket match everything. And DO NOT take much if any off of the intake runners because they are paper thin already. Just polish them if you must do something to them.
Also you can reshape the exhaust ports to a circular shape. Round exhaust ports are the best. Google it for some intresting info on that.If you go all out like I did and polish the combustion chambers then you'll need to be real carefull of the valve seats and valves. Take you're time. After you're done finish everything up with a wire wheel brush on a high speed air gun. Then everything will be smooth as glass.