You have to cut off one frame of animation and align each frame properly, since the ratio is off a bit (can't just reduce the whole thing by 20% or something and call it finished, parts of each character frame would overlap other frame grids)

Edit: Though now that I look at, might be easier than at first glance - if reduced by 66%/62% it gives a pretty close estimate, now it's just a matter of alignment

Edit 2: Blurry as heck though, looks awful