Well, I just restored my buckets with the legendary rallye seat kit. Fantastic fit with no problems what so ever. Make sure the material is at or above room temperature before starting as it will make the material a little more pliable. As well, there are several videos on YouTube restoring 1969 Barracuda bucket seats that are really helpful.
Good luck with it, you will be very happy with the Legendary products.
Here's my seats.
View attachment 1715144050 View attachment 1715144051
View attachment 1715144052