Hey guys I'm changing my open m78 diff to a m86 lsd, only problem I don't know what driveline to use, my cars a ford falcon BF xt Manual, I was told it had a t5gearbox not 100% sure though any help would be appreciated thanks!

Driveline includes; Gearbox, Tailshaft and Diff.

I assume that you are asking about which tailshaft you should be using?

If your gearbox is a 5 speed manual, then it will be the T5.