Help needed to sync new mixes to old music videos

[BeanMan]

Could someone please advise me on the best way to resync new 5.1 music mixes to old music videos.
Most of the mixes will be from Sony Digital multitracks with the exception of a few on analogue.
Mixing will be to ProTools of course. The old videos are various formats but mostly from analogue video masters both 1inch and 2inch. They will be transferred to digibeta after clean up etc, All the old videos will have guide audio tracks for reference. I know I could use time stretch to match (even in sections) but I'm afraid this will degrade the sound. Any other ways? I think I read somewhere about using 2 Pro Tool setups for this type of resync. How is this acheived?
Thanks in advance for your time.

[TLmix]

Have the tempos of the song changed? If not, it should just be a matter of lining up the new mix with the old in PT, unless there was a pull down in the original.... probably not though. If so, just pull down your analog machine..... i.e. if it has 30ndf on it... video ref the lynx... pulling it down to 29.97. If you have to do a digi transfer, you can use the pull up/ down in the PT session set up and the SRC in the 192.

Hope this helps..

TL