273 Rocker Arm to Shaft Clearance

I dunno. 0.003" is an acceptable clearance(admittedly, on the loose side) for a connecting rod bearing, what makes the rocker arm to shaft clearance so far outside the norm or more critical than a con rod bearing clearance? Hey, if it means that much to you, spend all you want. It makes no difference to me. At what point, why don't you just get some Harland Sharp's and call it good enough?