With the rings off,insert the piston into the bottom of the cylinder. Hold the piston skirt flush with the cylinder wall and see what size feeler gauge can fit into the gap between between the piston skirt and cylinder on the opposite side. This is just a rough way to check piston to cylinder clearance without have to use bore gauges and a micrometer. Here's a video on this.

 

OHHH...da no problem. I got all that stuff. I used to be a machinist