If this is one problem you can see there are sure to be more once you get the head off. I would pull the heads and rebuild them, no need to spend time and money on something that may only last 5000 miles. I know money is tight but realistically you could be throwing good money after bad if you don't do it right the first time.
This is how I justify these kinds of things to myself;
-A die grinder could accidentally fall into the ports and open them up.
-Larger valves might find their way into the valve guide and inadvertantly create more power.
-You know you want to see the tops of the pistons.
-Since the intake has to come off, the casting could become porous and need replacing with an aluminum one...four barrel of course!
-The original cast iron exhaust manifolds could be full of carbon requiring replacement with tubular steel versions. Hey you ever price an original cast iron manifold from the factory? Headers are cheap by comparison.
-Pistons carboned up and need to be scraped clean meaning you can run lower octane fuel saving you $$$$.
Ahhhh who am I trying to kid, You must replace those heads with 427 low riser versions. The car will not run right without them.