Even if you cut the piston, you should rebalance the crank to match; but it will be "small"

I bet you are hitting at the piston pin boss area. In this pic, these pistons are 0.150" thick in that spot. Strengh and thickness vary with design. But I wouldn't take 0.060" off of these (ie .090").

Are you using a 6.76" rod length or somthing shorter?