Fusing Two Images Side by Side

	1) Open up your background image, (or the first image). Select All and Copy to the Clipboard.
	2) Open up your foreground image, (the second image).
	3) Click a Quick Mask Button and apply a Gradient in the direction you want to blend the first image to the second (from left-most to 1/4 from right, for my example) In the layer palette in the lower right, white area will show see-through, while the black area will keep its image.
	4) Back to Normal Mode, and Edit > Paste Into to apply the selection into the second image.