Question for Owners of Cricket .22 AND .25

On all the synthetics, the compact .177,.22 standard, and the .25 the stocks are identical. The .177 and.22 have a single attaching bolt in front of the trigger. They both have a blank or non attaching screw in the pistol grip handle. The .25 the screw in the handle is functional and that secures to a button on the bottom of the airtube. There is a casting space in all three stocks to accommodate that button. The .177 and .22 shorter screw ends inside the handle. These are all older guns with the numerical fill gauge,