There could be a couple of issues that could have an effect on the gear mesh. First could be that the distributor gear isn't located on the dist. shaft in the correct position or there is too much up and down clearance on the dist shaft. Another is that the dist. bearings/bushings are worn causing too much side play. There is a spec. that determines the correct depth of the dist gear. This is the clearance at the bottom of the distributor's gear and the engine's block. Excessive torque on the bolt for the distributor hold down bracket may also enter the equation.
Second could be excessive wear on the camshaft thrust plate, cam sprocket and the camshaft itself, where it makes contact with the plate. Wear at these points contribute to excessive cam end play. This is where the reference to the cam "walking" comes in. There is a spec for the amount of clearance, (End Play). You may need to use a thrust plate that is made of a harder material. There is a severe duty thrust plate that is made from steel rather than cast iron. One of these should be available for the Cleveland series engines. If, by chance you have retrofitted a roller camshaft, it may be that the use of a cast iron dist. gear is the source of your problem. If this is the case, a hardened steel, bronze or plastic composite dist. gear will need to be installed. | 
