The SBC V8 feature that makes its heads semi-practical is the fact that the bore pitch (distance between adjacent cylinder centerlines) is the same for the later L6* and V8 at 4.40". The bolts are way off.
* this is why the 235 etc. isn't so simple. Nothing else has that staggered bore pitch (although many older engines have stagger including the slant 6, GMC, Ply-Do, Pontiac, etc.), so in addition to all of the other work you also need either surgery just to move the chambers over the cylinders, or partially shroud the chambers.
