I assume you have the 2 video files (or do they need to be swiped from those sites) I did not check to see if either are downloadable or are streaming (in which case are not steal able)
Also, when added together and outputted to your final format - a little more quality will be lost (unless you have the original high res versions/not the web ready ones at your links)
Any questions PM me.
Cheers,
Jeremy