Taking Cotten's comments as definitive as to base plates, how about the distortion to the top of the bore caused by the weird head-bolt pattern of all side-valve motors (45, UL, Chief, etc.)?? There must be distortion of the deck surface locally due to head-bolt torque. We're going to work on this without the expense of a full torque plate (one that would simulate a complete head casting, same bolt perch depth, with access hole for boring bar). The thought is: distortion of the casting can be simulated by installing the correct bolt, washer, etc. and a spacer the same thickness as the head casting at that point. It won't have the advantage of simulating the stiffening of the casting caused by attachment of the head or full torque plate, but should still "bulge" the bore locally where the distortion would affect ring seating. Obviously, only the 4 (45) or 5 (UL) bolts near the bore itself are affected. Comments? Thanks!