He's free!  However, there was a cost.  I successfully slid the thin white cardboard beneath him and the Tupperware container but he started moving and I clamped the lid on tighter and in the process, CUT OFF HIS TAIL!!!!!!  The tail continued to move for about 2 minutes!  Went out the front door with him and placed the container, gecko and white cardboard on the front porch and lifted the container.  He didn't MOVE!!!!  I thought he would run away.  Twenty minutes later, he's still there on the white cardboard in the sun!!!  Maybe he's in shock from having his tail cut off....poor thing!!!  I do not think I have a future in critter rescue unless it’s maim and rescue...