The endplay should be checked before removing the crankshaft. With the stem aligned with the crankshaft, a dial indicator needs to be set up so that it touches one of the throw arms. After pushing the crankshaft completely backward, zero the dial indicator. Then pry the crankshaft as far forward as possible and read on dial indicator. This movement determines how much endplay is. If it exceeds what's prescribed, examine the thrust surfaces on the crankshafts for wear. If no evidence of wear exists, new main bearings would correct this clearance problem. In case you do not have a dial indicator, you can use feeler gauges instead. When prying or pushing on it with care, make sure to move the crankshaft until it reaches at extreme front of engine block. The clearance between the front face of thrust main bearing and the crankshaft should be measured using feeler gauges. Do these bearing caps have any marks indicating their locations. It is from front to rear numbering them consecutively. If there are no such marks they could be numbered by number stamping dies or even center punch in case they are not cast-in top of the main bearing caps showing any arrow out pointing to front side of engine block. One-quarter turn at a time each should be loosened every one of main bearing cap bolts until they can easily be taken out by plain hand. Thus each cap should then be carefully tapped using soft-faced hammer and separated from engine block when necessary; bolts could remove caps if needed. Well, as long as you don't lose them along with corresponding bearing caps you don't need to worry about dropping those inserts. Upon lifting it up cautiously from engine block assisted by someone else due its weighty nature, the best way could involve having an assistant around in order for ease lifting of this entire crankshaft. The respective locations where each cap belongs can easily guided by looking at them while holding bearing inserts within engine block and main bearing caps are returned by tightening their bolts with fingers only.