The thickness of the crankcase cover gasket sets the endplay of the crankshaft. You need to use one or more gaskets of selected thickness to end up with an endfloat of 0.002"-0.008". This manual tells you how to go about setting this up:
http://www.tpub.com/content/recoveryvehicles/TM-5-4240-501-14P/css/TM-5-4240-501-14P_243.htm