Porting Magnum Heads

look at the 318 head porting post at the top of this forum "small block tech". Also, there is an article from one of the mopar magazines about magnum head porting.
Blending the intake bowl....for street use they say the bowl diameter should be around 85-88% of intake valve diameter based on maximum valve lift. So grind down an old valve to the diameter you need, or buy a set of calipers, or make a cardboard shape of the correct diameter and maybe with an end that fits into the valve guide hole to center the cardboard.
I would say you could blend the bowl shape some more. There are alot of details...do some more internet research and many questions will be answered.