Go into the x's with a good port job,if you haven't done it already replace the valves.If your guides are good keeep the 3/8 stem and use a quailty stainless item non tulip,use a nailhead or slight ramp style profile .This will raise compression a bit as the factory tulips in the chamber area increase volume.While you are there mill the heads to finish up between 55-60cc's.Use a quality flat top flat piston to end up with 10:1 compression with your head combo.Run a solid cam around 520-530 lift and
240-245@50. Street and little strip use the Air Gap or with more strip use the Victor or Strip Dominator and 750 vac or 750 double pumper.This engine makes its power in the heads,camshaft and needs a minimum of 9:5 to 1 or better.
Sorry, I meant to address this reply to the original poster.Also for the purposes of making some bonus additional power use headers,you can put your original manifolds back on if you sell the car to a collector.