Crankshaft End Play

[Mains52]

So i was messing with my 5.3 yesterday and was wondering if the crank had any up/down/ side to side play and although it didnt it did have some front to back movement. I know it is supposed to have a little bit but how much is too much? the engine supposedly has 175k on it and was pulled from a tahoe for oil pressure problems. I would like to just rebuild it but for the cost of a budget rebuild you can buy another JY engine right now. Thanks