How can I run 2 x logos & 1 graphic as overlay/super for entire 40 min clip?

I'm putting together a montage video loop comprising of stills, videos, graphics, etc, for a major event we're going to, and I  want to place a permanent super over all the material.

This would consist of 2 separate logos and one graphic super. They all reside in the same location during the  40 min video.

I thought I could turn them into a subsequence and just drop that on to a single video track, but then realised you can't extend this material once it's turned into a subsequence.

I know this has to be simple, and I don't want to tie up 3 video tracks, so some advice here would be appreciated as I  just don't use PP enough to become a power user... there are really long breaks in between using this great software.