Double/ expanding effect

From the research stages I found that disco videos tend to be heavily edited particularly during the performance stages.In order to create the duplicated effect, the original clip has been duplicated and placed above the original clip with the opacity turns down to 40%. at first I just positioned the overlayed  clip at (FIND NUMBERS ON PREMIER), however this created a black line from where the the top clip was displaced and didn't fit the bottom clip. Therefore, the overlayed clip was made to expand and move across to the left at two separate keyframes across the clip, resulting in the disappearance of the black overlapping line.