Just my opinion, but as they are hand stitched i would not trim them first because the stitching could come loose.
If I were doing this, i would add a wide sashing around each one (several inches wide) - each sashing to be cut to the necessary length for that side of that block..... then trim that down so that all the blocks would be the same size. I think the slight variation would be lost in the overall quilt and when it was quilted.
BEST OF LUCK....this is such a treasure from your past.