Ok I got ya. If you want to keep the stock linkage and reuse as much as possible and still use the t5, they make adapter plates that go inbetween your transmission and bellhousing which allows you to use all the other stock stuff. You would still need the trans crossmember, yoke, and to get your driveshaft shortened.
Mustangs Plus*::*EFI & T-5 Conversions*::*T-5 Bell Housing Spacer/Adapters*::*1965-70 6-Bolt Bell Housing Adapter