Small block crankshaft endplay

I know their are several threads asking the same question, and I am sure that I know the answer to this question. My son is working on his '71 Plymouth valiant, its a multi issued repair. His steering gear box leaks like a sive, so he's got firm feel building him a stage two unit, replacing the pump as well, new dual piston brakes, steering linkages, sway bar, etc. Well on top of that, the timing chain cover leaks heavily, so he pulled the radiator, belts, pulleys, etc. He asked me to look at how much crankshaft endplay he has front to back. Now the crankshaft dampener bolt is removed, but when you grab the balancer the entire crankshaft moves probably 1/2" front to back, you can see the torque converter through the starter opening and the only thing that stops the crankshaft travel is the torque converter hitting the back of the block or the converter hitting the timing cover. I told him that I cant remember ever seeing so much endplay. Now, maybe because the dampener bolt is removed its moving more than it should or normally would. But I think the fact that all the internals are still in there, that's excessive to say the least. But I told him that I would ask what the general consensus is. Original numbers engine, never been out of the car or rebuilt. I am thinking it's time for it to be rebuilt? What's the thoughts on this.