Easy way to check piston to valve clearance

[Rickster289FIA]

You can run the piston to TDC and then remove the springs and retainer (with a valve compressor). Once they are off, wrapp a thick rubber band around the valve stem until really tight to make sure the valve does not drop into the cylinder. Then you can add a lighter checking spring and start checking witha dial indicator in 2 degree increments from 15-20 degrees before to 15-20 degrees after TDC. Once you get your measurements, you can replace your spring and retainer by using a compressed air adapter that screws into your spark plug hole, or others have used a piece of soft rope pushed into the cylinder through the spark plug hole to hold the valve completely closed while replacing the spring and retainer.