If you are just looking to upgrade to a stock T5, you will need the
tranny, bell, and shifter at minimum.
I would highly recomend replacing the adjustable cable set-up in the '79 with the later style cable and quadrant.
As for the clutch, if you are planning on an upgrade, you will need a 28oz flywheel that will accept the '86 and up 10.5" clutch and metric preassure plate bolts. You should be able to get the right flywheel from Ford Racing for a $100 or so. The bolts you can get from the dealer.