[T16]

Yes.
What is your plan for all the front suspension?
You need different hubs, modified lower arms, shocks, springs, ARB links, all the rear suspension is very different, you would need to customise the lot, or procure three sets of arms, springs, shocks, arb links, hubs, bushes, shocks, discs, calipers, pads, hoses, clips, the list goes on.

If you plan to fabricate the lot, there won't really be any ZT left.
Might as well get a mustang/whatever, and drop a ZT bodyshell on top.

Not to mention the HVAC, different compressor, pipes, hoses, Blower assembly, ECUs, Hot water valve.
I am experiencing chest pains simply even thinking about the hassle involved. Then you have the Ford ECU, combined with the Rover Gateway ECU, and having to integrate the two or run some custom ECU and still integrate to the Rover Gateway... No idea how this could be done, maybe it can be though.

Things are different with an old old classic, maybe Mk1 Escort etc as things are so simple, but the ZT is in that awkward area where its old, but "new" in terms of being a classic, and has so much modern car manufacturer complexity.

I'd say next best thing might be a genuine V8 (there have been a few cheap ropey project cars going for sale recently) and shove a 5L engine and 6 speed box in, or modify the 4.6L. Lord knows, just doing the latter is enough work too!