We used an XJ6 Jaguar in ours.

That was about fifteen years back now, and details are a bit hazy; but I do remember it as a virtual bolt-in swap.

I just went and had another look at it...and could see that there were no major dramas.
Very straightforward.
From memory it also lowered the car about three/three and a half inches.

And it gave us disc brakes...a definite plus!

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