Replacing lost source footage of edited video with same footage that was recaptured?

Hey I have a nearly finished edited music video where all of the source footage came from one digitatized 2 hour capture of a super high 8 video tape that I cut down. My external hard drive with the source video broke, so I no longer can access the footage that I edited in the PP project. I redigitized the same hi 8 tape, the only difference being a slight variation in the start and end times of the capture.

Do y'all have any advice for the best way for me to go about trying to replace the lost footage with the "new footage" while maintaining the edits and the sync of PP project that was based off the lost footage? 

My main idea is just trial and error of trying to replace the source footage with the new footage by trimming the start time until the video seems to be in sync again with the edits.

any advice is appreciated, sorry if my language was confusing, thank you.