Clearance is determined by the cam being used. If you think it has a stock cam, set them at .014" intake and .016" exhaust. If the head has it's original rocker arms, they are 1.25:1 ratio, so valve clearance is 1.25 times stock settings. You could also check the present clearances and assume they are close to what they should be, and adjust any that are far off. Now might be a good time to re-torque the head.
