Just by looking at it visually, I can tell it's too wide.
1 = 194px × 159px x 46.72 KB
2 = 284px × 162px x 77.41 KB
3 = 194px × 159px x 47.17 KB
So 672 px wide (limit is 500 px) and 171.3 KB (limit is 60 KB). So definitely too wide, and the middle image on it's own is too heavy. Even without it, your sig would be too heavy as the left and right images would total 93.89 KB.