As I recall, 3916(accually what it says on the web site) is , or should be, some replacement berrings for part number 3913(light weight diff assembly). So those should be the ones. As for part 6909, that is a diff berring(possibally for a different car, or the steel outdrive diffs) but there are many ae cars with relitivally the same dimentions for diff berrings, but are not for the TC3
I will try the 3916 berrings this weekend, and post the results. I did see the berrings that are for the plastic outdrives, but I do not know the part number.