Well I have lots of experience with this issue, i have an 03 crew long bed 4x4 that had been dusted, and #8 took most of the beating. Its seems that #8 is always a problem in most engines, it seems to wear the most due to not being fueled properly. Its Symptoms were more than usual blow by, lower power, failed cylinder contribution test, and lower compression in #8. It ran ok , I drove it everyday and it was not as good on fuel mileage as it had been. One day it got a knock in the piston area of #8 so it was time to fix it.
Now the bad news, when I tore it down to rebuild it I found that the wear from the dusting had caused excessive wear in the cylinders, mainly 6,7,and 8. 8 had such a bad ring groove it had broken the ring and the land on the piston and was eating the cylinder wall badly. 6 was worn next worse, and 7 was not far behind. The rest of the cylinders were ok and would have cleaned at .030 over. For the record .030 over is as far as you can go on a 7.3. Now I had to get a new block, so I ordered a supposedly good core from the internet, I got it and all the cylinders in it were good but 8. So I just sleeved 8 and built that one. Of course the turbo was destroyed too, the fins were rounded and worn badly, good reason for a wicked wheel and a rebuild.
I wish you the best, hope you have better luck than me, but a hasty rebuild could save trouble in the long run.