If I were you I would head to the local bone-yard and grab some 993 casting truck motor heads. They usually have small 1.94 intake valves(instead of 2.02) and they shouldn't cost more than $100 or so, depending on where you are, I guess. Even the older ones w/out hardened seats will work for years( I have tried it) in a pinch. Of course Stu is right, heads are critical, you are smart enough to ask if you should try it I think you'll be fine if you listen to the majority of the old dudes, even some guys at the junk yard know some stuff. Even if you have a set of great 305 heads you will get sick of wishing you'd have scrounged a bit. Small Blocks have been around much longer than weve been alive and I think they can make or break a person. AND... 1.94s do make torque! This is a great place to learn keep reading and just make sure to do your research on the road with something that won't have you pouring in 104 octane booster additive by the gallon=]. Oh yeah and the key to a good rebuild is the cleanliness of your components, clean it all 10 times!