Hello I have been helping a friend assemble a 292 , I have noticed lines on the cylinder walls you can not feel them with your finger . They appeared after the piston was installed and the engine was rotated to install the next piston . The engine is 40 over with new pistons and matching rings there was no file work done on the rings so I do not thing there is a sharp edge.The cylinders and pistons were well oiled when they were installed. Like I said I do not feel the line but I am wondering what will happen when the engine is fired up. Every thing was very clean so I don’t think any debris is involved. Not all the cylinder show the lines. If I get a chance I will post some photos but quick search on the net I have found a lot of people complaining of marks on the cylinder walls after new rings and pistons were installed in freshly bored and honed engine.