It doesn't really matter what model/year of ford that the diff comes from, it will not fit the Torana without being converted.
The leaf spring mounts will need to be cut off and some suitable Torana mounts welded on (in the correct place, of course), then the ends get cut off the housing and replaced, shortening it at the same time, then you either fit billet axles or some other axles that are the correct length, size, spline count, stud pattern, etc. and suit the brake package of your choice.
If you're going down that road, just find a conversion place and get them to supply everything ready to go, some may not even take a donor diff.
All that costs money, as Rexy said, probably around $3k~$3.5k all up.
If you're on a budget, look around for a second-hand 9" out of a Torana, there would be thousands of them about so it's just a question of finding one, although finding one from a UC will make your task a lot harder (different suspension mounting points from the earlier models).
You may pick one up for around $2k but you might not get the exact ratio you want, so factor that into the budget. Also, people don't fit 9" diffs to drive to the supermarket on Sunday so just be aware that you might be buying something that's been used and abused.
Edited by Bigfella237, 01 October 2021 - 01:06 PM.