I'm using Movie Maker 2012 Build 16.4.3528.0331

I just got a dual dashcam setup for my car. Currently the two cameras are recorded in 5 minute clips and records both the front and rear cameras as separate video files that are perfectly synchronized with each other. My problem is trying to figure out how to overlay the rear camera into the corner of the front camera's video with a picture in picture setup.

I've searched online and found a few ways to do this but nothing seems to actually match the instructions I've found.

Do I need to buy a video editing package to do what I want or is there an add-in for movie maker that will allow me to use PIP.