I am rebuilding a lower unit whose pinion gear broke in half. Had to replace the driveshaft and gears with a used set. Replaced the driveshaft thrust bearing (conical) and put it together with the old shim pack. Installed in the lower unit, the driveshaft is quite loose in the bearing - actually moves up and down about 1/32" or so - is this OK? I have been told that the driveshaft should have some slack in it, but how much?